SARS-CoV-2 infection in adult liver transplantation recipients: a systematic review of risk factors for mortality and immunosuppression role

OBJECTIVE

Data on mortality, immunosuppression, and vaccination role regarding liver transplant (LT) recipients affected by COVID-19 are still under debate. This study aims to identify risk factors for mortality and the role of immunosuppression in COVID-19 LT recipients.

MATERIALS AND METHODS

A systematic review of SARS-CoV-2 infection in LT recipients was performed. The primary outcomes were risk factors for mortality, the role of immunosuppression and vaccination. A meta-analysis was not performed as there was a different metric of the same outcome (mortality) and a lack of a control group in most studies.

RESULTS

Overall, 1,343 LT recipients of 1,810 SOT were included, and data on mortality were available for 1,110 liver transplant recipients with SARS-CoV-2 infection. Mortality ranged between 0-37%. Risk factors of mortality were age >60 years, Mofetil (MMF) use, extra-hepatic solid tumour, Charlson Comorbidity Index, male sex, dyspnoea at diagnosis, higher baseline serum creatinine, congestive heart failure, chronic lung disease, chronic kidney disease, diabetes, BMI >30. Only 51% of 233 LT patients presented a positive response after vaccination, and older age (>65y) and MMF use were associated with lower antibodies. Tacrolimus (TAC) was identified as a protective factor for mortality.

CONCLUSIONS

Liver transplant patients present additional risk factors of mortality related to immunosuppression. Immunosuppression role in the progression to severe infection and mortality may correlate with different drugs. Moreover, fully vaccinated patients have a lower risk of developing severe COVID-19. The present research suggests safely using TAC and reducing MMF use during the COVID-19 pandemic.

Management of Small Bowel Obstruction (SBO) in older adults (>80 years): a propensity score-matched analysis on predictive factors for a (un)successful non-operative management (NOM)

OBJECTIVE

Small Bowel Obstruction (SBO) is a common emergency in older patients. The most appropriate treatment strategy is still matter of debate. The aim of this study was to compare a non-operative management (NOM) vs. a surgical procedure for patients ≥ 80 years with SBO.

PATIENTS AND METHODS

All patients ≥ 80 years admitted to our Emergency Department (ED) for SBO between January 1st, 2015, and December 31st, 2020 were included in this study. In order to correct for baseline covariates and factors associated to clinical management, we used a 1:1 propensity score matching (PSM) analysis. The primary outcome was to compare the overall in-hospital mortality. Secondary outcomes included occurrence of major complications and in-hospital length of stay (LOS).

RESULTS

A total of 561 patients were enrolled. After propensity score matching (PSM) analysis, 302 patients (151 each group) were included in the analysis. Mortality did not differ between the two groups. After PSM mechanical ventilation, sepsis, cumulative major complications, and LOS were significantly higher in the operative treatment group [15.9% vs. 1.5%, 9.4% vs. 4.1%, 27.6% vs. 19.2%, and 9.4 (6.4-14.3) days vs. 8.1 (4.5-13.3) days, respectively; p<0.001, p=0.013, p=0.025, and p=0.003, respectively].

CONCLUSIONS

In patients ≥ 80 years with SBO, a NOM could yield similar results, in terms of overall mortality, compared to a surgical management. Thus, particularly in patients with multiple comorbidities or functional impairments, a conservative approach should always be considered.

Acute intestinal ischemia in patients with COVID-19: single-centre experience and literature review

OBJECTIVE

Acute Intestinal ischemia (AII) may involve the small and/or large bowel after any process affecting intestinal blood flow. COVID-19-related gastrointestinal manifestations, including AII, have been attributed to pharmacologic effects, metabolic disorders in ICU patients and other opportunistic colonic pathogens. AII in COVID-19 patients may be due also to "viral enteropathy" and  SARS-CoV-2-induced small vessel thrombosis. A critical appraisal of personal experience regarding COVID-19 and AII was carried out comparing this with a systematic literature review of published series.

PATIENTS AND METHODS

  A retrospective observational clinical cohort study and a systematic literature review including only COVID-19 positive patients with acute arterial or venous intestinal ischemia were performed. The primary endpoint of the study was the mortality rate. Secondary endpoints were occurrence of major complications and length of hospital stay.

RESULTS

Patient mean age was 62.9±14.9, with a prevalence of male gender (23 male, 72% vs. 9 female, 28%). The mean Charlson Comorbidity Index was 3.1±2.7. Surgery was performed in 24/32 patients (75.0%), with a mean delay time from admission to surgery of 6.0 ±5.6 days. Small bowel ischemia was confirmed to be the most common finding at surgical exploration (22/24, 91.7%). Acute abdomen at admission to the ED (Group 1) was observed in 10 (31.2%) cases, while 16 (50%) patients developed an acute abdomen condition during hospitalization (Group 2) for SARS-CoV-2 infection.

CONCLUSIONS

Our literature review showed how intestinal ischemia in patients with SARS-CoV-2 has been reported all over the world. The majority of the patients have a high CCI with multiple comorbidities, above all hypertension and cardiovascular disease. GI symptoms were not always present at the admission. A high level of suspicion for intestinal ischemia should be maintained in COVID-19 patients presenting with GI symptoms or with incremental abdominal pain. Nevertheless, a prompt thromboelastogram and laboratory test may confirm the need of improving and fastening the use of anticoagulants and trigger an extended indication for early abdominal CECT in patients with suggestive symptoms or biochemical markers of intestinal ischemia.

Surgical emergencies during SARS-CoV-2 pandemic lockdown: what happened?

OBJECTIVE

The pandemic from SARS-CoV-2 is having a profound impact on daily life of a large part of world population. Italy was the first Western country to impose a general lockdown to its citizens. Implications of these measures on several aspects of public health remain unknown. The aim of this study was to investigate the effects of the lockdown on surgical emergencies volumes and care in a large, tertiary referral center.

MATERIALS AND METHODS

Electronic medical records of all patients visited in our Emergency Department (ED) and admitted in a surgical ward from February 21st 2020 to May 3rd 2020 were collected, analyzed and compared with the same periods of 2019 and 2018 and a cross-sectional study was performed.

RESULTS

Number of surgical admissions dropped significantly in 2020 with respect to the same periods of 2019 and 2018, by almost 50%. The percentage distribution of admissions in different surgical wards did not change over the three years. Time from triage to operating room significantly reduced in 2020 respect to 2019 and 2018 (p<0.001).

CONCLUSIONS

The lockdown in Italy due to SARS-CoV-2 pandemic arguably represents the largest social experiment in modern times. Data provided by our study provide useful information to health authorities and policymakers about the effects of activity restriction on surgical accesses and changing epidemiology due to an exceptional external event.

Redo-laparoscopy in the management of complications after laparoscopic colorectal surgery: a systematic review and meta-analysis of surgical outcomes

BACKGROUND

The laparoscopic approach for colorectal surgery has gradually become widely accepted for the treatment of both benign and malignant diseases thanks to its several advantages over the open approach. However, it is associated with the same potential postoperative complications. Some recent studies have analyzed the potential role of laparoscopy in early diagnosis and management of complications following laparoscopic colorectal surgery. The aim of this systematic review was to investigate the outcomes of redo-laparoscopy (RL) for the management of early postoperative complications following laparoscopic colorectal surgery, focusing on length of stay, morbidity and mortality.

METHODS

A systematic review of the literature was performed according to the preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines through MEDLINE (PubMed), Embase and Google Scholar from January 1990 to December 2019. The main outcomes examined were conversion rate, length of hospital stay, postoperative morbidity and mortality rates. A meta-analysis of all eligible studies was then conducted and forest plots were generated.

RESULTS

A total of 19 studies involving 1394 patients who required reoperation after laparoscopic colorectal resection were included. In 539 (38.2%) of these patients, a laparoscopic approach was adopted. The most common indication for returning to the operating theater was anastomotic leakage (64.4% of all redo-surgeries, 67.7% of RL) and the most common type of intervention performed in RL was diverting stoma with or without anastomotic repair/redo (47.1%). Nine studies were included in the pooled analysis. The mean length of stay was significantly shorter in the RL group than in the redo-open one (WMD = - 0.90; 95% CI - 1.04 to - 0.76; Z =  - 12,6; p < 0.001). A significantly lower risk of mortality was observed in the RL cohort (OR =  - 0.91; 95% CI - 1.58 to - 0.23; Z = - 2.62; p = 0.009).

CONCLUSIONS

Laparoscopy is a valid and effective approach for the treatment of complications following laparoscopic primary colorectal surgery thanks to it is well-established advantages over the open approach, which remain noticeable even in redo-surgeries.

Percutaneous cholecystostomy in the treatment of acute cholecystitis: is there still a role? A 20-year literature review

OBJECTIVE

Percutaneous cholecystostomy (PC) is used for the treatment of acute cholecystitis in patients with high surgical risk due to the severity of cholecystitis and/or the underlying acute or chronic medical comorbidities. The evidence for this strategy is unclear.

MATERIALS AND METHODS

We searched PubMed and the Cochrane databases for English-language studies published from January 1979 through December 31, 2019, for randomized clinical trials (RCTs), meta-analyses, systematic reviews, and observational studies.

RESULTS

The two randomized studies that have compared PC with cholecystectomy (CCY) or conservative treatment have shown that the clinical outcomes did not differ significantly between the groups. Similar results have been found in the large majority of retrospective cohorts or single-center studies that have compared PC with CCY.

CONCLUSIONS

PC does not seem to offer any benefit compared with CCY in the treatment of acute cholecystitis in patients with high surgical risk due to the severity of cholecystitis and/or the underlying acute or chronic medical comorbidities. A large, prospective, randomized study that compares percutaneous PC and CCY in patients with high surgical risk and/or moderate to severe cholecystitis is warranted.

Early recognition of methicillin-resistant Staphylococcus aureus surgical site infections using risk and protective factors identified by a group of Italian surgeons through Delphi method

BACKGROUND

Surgical site infections (SSIs) constitute a major clinical problem in terms of morbidity, mortality, duration of hospital stay, and overall costs. The bacterial pathogens implicated most frequently are Streptococcus pyogenes (S. pyogenes) and Staphylococcus aureus (S. aureus). The incidence of methicillin-resistant S. aureus (MRSA) SSIs is increasing significantly. Since these infections have a significant impact on hospital budgets and patients' health, their diagnosis must be anticipated and therapy improved. The first step should be to evaluate risk factors for MRSA SSIs.

METHODS

Through a literature review, we identified possible major and minor risk factors for, and protective factors against MRSA SSIs. We then submitted statements on these factors to 228 Italian surgeons to determine, using the Delphi method, the degree of consensus regarding their importance. The consensus was rated as positive if >80% of the voters agreed with a statement and as negative if >80% of the voters disagreed. In other cases, no consensus was reached.

RESULTS

There was positive consensus that sepsis, >2 weeks of hospitalization, age >75 years, colonization by MRSA, and diabetes were major risk factors for MRSA SSIs. Other possible major risk factors, on which a consensus was not reached, e.g., prior antibiotic use, were considered minor risk factors. Other minor risk factors were identified. An adequate antibiotic prophylaxis, laparoscopic technique, and infection committee surveillance were considered protective factors against MRSA SSIs. All these factors might be used to build predictive criteria for identifying SSI due to MRSA.

CONCLUSIONS

In order to help to recognize and thus promptly initiate an adequate antibiotic therapy for MRSA SSIs, we designed a gradation of risk and protective factors. Validation, ideally prospective, of this score is now required. In the case of a SSI, if the risk that the infection is caused by MRSA is high, empiric antibiotic therapy should be started after debriding the wound and collecting material for culture.

Erratum to: Antimicrobials: a global alliance for optimizing their rational use in intra-abdominal infections (AGORA)

[This corrects the article DOI: 10.1186/s13017-016-0089-y.].

Focus on the prophylaxis, epidemiology and therapy of methicillin-resistant Staphylococcus aureus surgical site infections and a position paper on associated risk factors: the perspective of an Italian group of surgeons

BACKGROUND

The aim of this research was to study the epidemiology, microbiology, prophylaxis, and antibiotic therapy of surgical site infections (SSIs), especially those caused by methicillin-resistant Staphylococcus aureus (MRSA), and identify the risk factors for these infections. In Italy SSIs occur in about 5 % of all surgical procedures. They are predominantly caused by staphylococci, and 30 % of them are diagnosed after discharge. In every surgical specialty there are specific procedures more associated with SSIs.

METHODS

The authors conducted a systematic review of the literature on SSIs, especially MRSA infections, and used the Delphi method to identify risk factors for these resistant infections.

RESULTS

Risk factors associated with MRSA SSIs identified by the Delphi method were: patients from long-term care facilities, recent hospitalization (within the preceding 30 days), Charlson score > 5 points, chronic obstructive pulmonary disease and thoracic surgery, antibiotic therapy with beta-lactams (especially cephalosporins and carbapenem) and/or quinolones in the preceding 30 days, age 75 years or older, current duration of hospitalization >16 days, and surgery with prothesis implantation. Protective factors were adequate antibiotic prophylaxis, laparoscopic surgery and the presence of an active, in-hospital surveillance program for the control of infections. MRSA therapy, especially with agents that enable the patient's rapid discharge from hospital is described.

CONCLUSION

The prevention, identification and treatment of SSIs, especially those caused by MRSA, should be implemented in surgical units in order to improve clinical and economic outcomes.

Overextended Criteria Donors: Experience of an Italian Transplantation Center

The increasing gap between the number of patients who could benefit from liver transplantation and the number of available donors has fueled efforts to maximize the donor pool using marginal grafts that usually were discarded for transplantation. This study included data of all patients who received decreased donor liver grafts between January 2004 and January 2013 (n = 218) with the use of a prospectively collected database. Patients with acute liver failure, retransplantation, pediatric transplantation, and split liver transplantation were excluded. Donors were classified as standard donor (SD), extended criteria donor (ECD), and overextended criteria donor (OECD). The primary endpoints of the study were early allograft primary dysfunction (PDF), primary nonfunction (PNF), and patient survival (PS), whereas incidence of major postoperative complications was the secondary endpoint. In our series we demonstrated that OECD have similar outcome in terms of survival and incidence of complication after liver transplantation as ideal grafts.

Therapeutic management of peritonitis: a comprehensive guide for intensivists

PURPOSE

The management of peritonitis in critically ill patients is becoming increasingly complex due to their changing characteristics and the growing prevalence of multidrug-resistant (MDR) bacteria.

METHODS

A multidisciplinary panel summarizes the latest advances in the therapeutic management of these critically ill patients.

RESULTS

Appendicitis, cholecystitis and bowel perforation represent the majority of all community-acquired infections, while most cases of healthcare-associated infections occur following suture leaks and/or bowel perforation. The micro-organisms involved include a spectrum of Gram-positive and Gram-negative bacteria, as well as anaerobes and fungi. Healthcare-associated infections are associated with an increased likelihood of MDR pathogens. The key elements for success are early and optimal source control and adequate surgery and appropriate antibiotic therapy. Drainage, debridement, abdominal cleansing, irrigation, and control of the source of contamination are the major steps to ensure source control. In life-threatening situations, a "damage control" approach is the safest way to gain time and achieve stability. The initial empirical antiinfective therapy should be prescribed rapidly and must target all of the micro-organisms likely to be involved, including MDR bacteria and fungi, on the basis of the suspected risk factors. Dosage adjustment needs to be based on pharmacokinetic parameters. Supportive care includes pain management, optimization of ventilation, haemodynamic and fluid monitoring, improvement of renal function, nutrition and anticoagulation.

CONCLUSIONS

The majority of patients with peritonitis develop complications, including worsening of pre-existing organ dysfunction, surgical complications and healthcare-associated infections. The probability of postoperative complications must be taken into account in the decision-making process prior to surgery.

Fungal infections after liver transplantation: incidence and outcome

BACKGROUND

Fungal infections, although less frequent than bacterial infections, represent a severe comorbidity with an exponential increase in mortality rate in liver transplantation patients. The incidence of invasive fungal infections (IFIs) after solid organ transplantation ranges from 7% to 42%, with Candida spp. and Aspergillus spp. as the most common pathogens. Fungal infections in liver transplant recipients have been associated with poor outcome and mortality rates ranging from 65% to 90% for invasive aspergillosis and 30% to 50% for invasive candidiasis. The results largely depend on early diagnosis and early initiation of specific treatment for IFIs. Therefore, the diagnosis must be prompt, preferably based on microbiological data, both cultures and biomarkers, and/or based on clinical features and known risk factors.

MATERIALS AND METHODS

This study evaluated the incidence of fungal infections in patients after liver transplantation in our center between January 2003 and December 2012. The retrospective analysis of 215 consecutive liver transplantation patients was undertaken to estimate incidence, risk factors, and clinical courses of IFIs in the first 3 months after liver transplantation.

RESULTS

Candidemia and invasive candidiasis microbiologically proven were found in 26 patients (12%), whereas in 6 patients (2.8%) invasive fungal infections from other non-Candida fungi developed: Aspergillus (4 cases: 2 A fumigatus, 2 A terreus), Fusarium oxysporum (1 case), and Rhodotorula rubra (1 case). Two patients with Aspergillus and the patient with Fusarium died. The patient with Rhodotorula as well as 22 of the patients with candidemia (85%) survived. All of the episodes developed during the first 3 months posttransplantation. All cases have followed a previous polymicrobial bacterial infection (especially in the biliary tract) with large use of combined antibiotic therapies.

CONCLUSIONS

The rate of fungal infection was found to increase in parallel with the number of risk factors. Prophylactic strategies can decrease the risk of fungal infections. Early detection and treatment with adequate early empiric therapy is the key to obtaining a better outcome in liver transplantation patients.

Diagnosis and Management of Hepatic Artery Complications After Liver Transplantation

BACKGROUND

We assessed the usefulness of color Doppler imaging in diagnosis and monitoring hepatic artery complications after liver transplantation.

METHODS

Subjects were 421 liver transplant recipients who underwent serial ultrasound (US) color Doppler evaluations of the hepatic arteries after surgery.

RESULTS

We saw 4 hepatic arterial complications after liver transplantation (13 thrombosis, 29 stenosis, 2 kinking, 2 pseudo-aneurysm, and 2 pseudo-aneurysm rupture). All subjects underwent US color Doppler examination periodically after surgery. In 6 cases of early thrombosis, hepatic arterial obstruction was diagnosed with absence of Doppler signals; in the other 7 cases (late hepatic artery thrombosis), thrombosis was suspected for the presence of intra-parenchymal "tardus-parvus" waveforms. In all of the cases, computed tomography angiography showed obstruction of the main arterial trunk and the development of compensatory collateral circles (late hepatic artery thrombosis). In 10 of the 29 cases of stenosis, Doppler ultrasonography examination revealed stenotic tract and intra-hepatic tardus-parvus waveforms; in 17 stenosis cases, the site of stenosis could not be identified, but intra-parenchymal tardus-parvus waveforms were recorded. In 2 patients, hepatic artery stenosis occurred with ischemic complications.

CONCLUSIONS

The use of US color Doppler examination allows the early diagnosis of hepatic arterial complications after liver transplantation. Tardus-parvus waveforms indicated severe impairment of hepatic arterial perfusion from either thrombosis or severe stenosis. The presence of these indirect signs enhanced the accuracy of color Doppler diagnosis, and detection should prompt therapy.

Incidence of upper aerodigestive tract cancer after liver transplantation for alcoholic cirrhosis: a 10-year experience in an Italian center

INTRODUCTION

The aim of this study was to evaluate the incidence, clinical characteristics, treatment, and outcome of de novo tumors (DNT) of the upper aerodigestive tract in patients with alcoholic cirrhosis after orthotopic liver transplantation (OLT).

METHODS

Among 225 consecutive OLT performed between January 2002 and January 2012, a total of 205 patients received a first liver allograft. Eleven (4.9%) patients developed DNT (lung, pancreas, bowel, esophagus, larynx, tongue, tonsil, and lymphoma). Among these, we observed 5 patients with DNT of the upper aerodigestive tract.

RESULTS

The 5 patients with DNT of the upper aerodigestive tract underwent OLT for alcoholic cirrhosis. There were 4 men and 1 woman with a mean age at transplantation of 47 years. The mean period of alcohol abuse was 90 months. The tumors occurred after a mean post-transplantation time of 39 months. The immunosuppressive regimen included Tacrolimus, mTOR, mycophenolate mofetil (MMF), and low-dose steroids. We observed 2 cases of squamous cell carcinoma of the esophagus, 1 case of tonsillar cancer, 1 case of larynx carcinoma, and 1 case of tongue carcinoma. All patients underwent surgical excision. After surgery, 4 patients received chemotherapy and 2 patients radiotherapy. At present, among the 5 patients with DNT of the upper aerodigestive tract, only 2 are alive without disease and 1 is alive with a local recurrence.

CONCLUSION

The incidence of DNT of the upper aerodigestive tract after OLT is higher among patients receiving a transplant for alcoholic cirrhosis. This could be due to an additional effect of post-transplantation immunosuppression in patients exposed to alcohol before transplantation. We suggest a careful post-transplantation follow-up and more attention to improve early diagnosis.

Surveillance of bacterial and fungal infections in the postoperative period following liver transplantation: a series from 2005-2011

Orthotopic liver transplantation (OLT) is a life-saving procedure for the treatment of many end-stage diseases, but infectious and acute rejection episodes remain major causes of morbidity and mortality. Bacterial and fungal infections can be due to intra-abdominal, biliary, respiratory, urinary, wound, central venous catheters (CVC) or unknown sources. Using the computerized database of our microbiology laboratory, we analyzed all the bacterial and fungal infections in the first three months following OLT among 151 consecutive adult recipients at single center between January 2005 and December 2011. Samples included blood, bile CVC, urine, and bronchoalveolar lavage (BAL) specimen. Culture and identification of the isolated microorganisms was done in accordance with standard microbiological procedures. Three hundred thirteen samples from the above sites showed positive results for gram-positive cocci (n = 137; 43.8%), gram-negative rods (n = 156; 49.8%), and Candida species (n = 19; 6.1%). One patient (0.3%) experienced a CVC-related infection caused by Fusarium oxysporum. Bacterial and particularly biliary tract infections seem to play major roles in morbidity and mortality in the first three months following OLT. The major contributors to patient morbidity and mortality were candidemia and/or invasive candidiasis mainly from the biliary tract and/or CVC-related infections.

Incidence, management, and results of hepatic artery stenosis after liver transplantation in the era of donor to recipient match

INTRODUCTION

Hepatic artery stenosis (HAS) is an important complication after liver transplantation. However, studies are not conclusive in terms of definition, incidence, best treatment, and timing of intervention. The aim of this study was to evaluate the incidence of SSHA that occurred in a single center over the past 12 years, pointing out diagnostic and therapeutic strategies.

METHODS

The incidence of HAS was reviewed in 258 liver transplant recipients between January 1999 and December 2011. All patients underwent Doppler ultrasound (DUS) at fixed times. Multidetector computed tomographic angiography (MDCTA) was performed to confirm the DUS findings.

RESULTS

HAS occurred in 23 cases (9.3%). In all cases diagnosis was performed by DUS resulting in a sensitivity of 100% and a specificity of 99.6%. Based on DUS and MDCTA data integration, in 10 cases we adopted the "wait and see" strategy, whereas 13 patients underwent interventional radiology techniques.

CONCLUSION

DUS monitoring is efficacious in the diagnosis of HAS after liver transplantation. Interventional radiology procedures are safe and efficacious.

Factors predicting ischemic-type biliary lesions (ITBLs) after liver transplantation

Among biliary complications, ischemic-type biliary lesions (ITBLs) remain a major cause of morbidity in liver transplant recipients, significantly affecting the chance of survival of both patients and grafts. We retrospectively reviewed 10 years of prospectively collected donor and recipient data from April 2001 to April 2011. We evaluated the incidence of ITBL occurrence, exploring the possible predisposing factors, including donor and recipient data. Two hundred fifty-one grafts were harvested: 222 of them were transplanted at our institution, the remaining 29 (11.6%) discarded by our donor team as showing >40% macrovesicular steatosis. Mild-moderate (20%-40%) macrovesicular steatosis (P < .001) and cold ischemia time (P = .048) significantly increased the risk of ITBL, also as an independent risk factor after multivariate analysis.

Anidulafungin--a new therapeutic option for Candida infections in liver transplantation

INTRODUCTION

In the last years, the incidence of Candida infections in liver transplant recipients has increased with still higher morbidity and mortality. Anidulafungin, a new echinocandin that does not interfere with cytochrome p450, shows no need for dosage adjustment based upon renal or hepatic function or weight.

AIM

To analyze tolerance to and microbiologic and clinical efficacy of Anidulafungin to treat Candida infections in liver transplant patients.

MATERIALS AND METHODS

This phase 3b, prospective, open-label, single-center study focused on liver transplant patients with a suspected and/or diagnosed Candida infection. The patients received Anidulafungin intravenously, optionally followed by oral therapy with azoles. The primary endpoint was the global response at the end of therapy; secondary endpoints were the efficacy of intravenous therapy, 90-day survival, as well as tolerance for and interaction with immunosuppresants.

RESULTS

We considered 42 consecutive liver recipients transplanted between 2009 and 2010 among whom 13 (31%) were recruited for the study and four patients were treated with Anidulafungin as empirical therapy, six as preemptive therapy, and three as targeted treatment for documented candidemia (7.1%). The immunosuppressive regimen consisted of tacrolimus and low dose of steroids. The Candida species were: C albicans (50%), C glabrata (12.5%), C parapsilosis (12.5%), C krusei (12.5%), C lusitaniae (6.2%), C tropicalis (6.2%), and multiple others (25%). The principle site of isolation was the bile (53.8%), followed by the bloodstream (23.1%), central venous catheters (15.4%), bronchoalveolar lavage (15.4%), peritoneum (7.7%), and other locations (7.7%). Two patients (15.4%) died of severe sepsis with multiple organ failure. There was no alteration of hepatic enzymes, indices of cholestasis or changes in immunosuppressant drug levels.

CONCLUSION

Anidulafungin was an effective, safe, and well-tolerated drug. There were neither toxic effects to the grafts or adverse interactions with immunosuppresants.

Anidulafungin for the treatment of candidaemia/invasive candidiasis in selected critically ill patients

A prospective, multicentre, phase IIIb study with an exploratory, open-label design was conducted to evaluate efficacy and safety of anidulafungin for the treatment of candidaemia/invasive candidiasis (C/IC) in specific ICU patient populations. Adult ICU patients with confirmed C/IC meeting ≥1 of the following criteria were enrolled: post-abdominal surgery, solid tumour, renal/hepatic insufficiency, solid organ transplant, neutropaenia, and age ≥65 years. Patients received anidulafungin (200 mg on day 1, 100 mg/day thereafter) for 10–42 days, optionally followed by oral voriconazole/fluconazole. The primary efficacy endpoint was global (clinical and microbiological) response at the end of all therapy (EOT). Secondary endpoints included global response at the end of intravenous therapy (EOIVT) and at 2 and 6 weeks post-EOT, survival at day 90, and incidence of adverse events (AEs). The primary efficacy analysis was performed in the modified intent-to-treat (MITT) population, excluding unknown/missing responses. The safety and MITT populations consisted of 216 and 170 patients, respectively. The most common pathogens were Candida albicans (55.9%), C. glabrata (14.7%) and C. parapsilosis (10.0%). Global success was 69.5% (107/154; 95% CI, 61.6–76.6) at EOT, 70.7% (111/157) at EOIVT, 60.2% (77/128) at 2 weeks post-EOT, and 50.5% (55/109) at 6 weeks post-EOT. When unknown/missing responses were included as failures, the respective success rates were 62.9%, 65.3%, 45.3% and 32.4%. Survival at day 90 was 53.8%. Treatment-related AEs occurred in 33/216 (15.3%) patients, four (1.9%) of whom had serious AEs. Anidulafungin was effective, safe and well tolerated for the treatment of C/IC in selected groups of ICU patients.

Diagnosis and management of skin and soft-tissue infections (SSTI): a literature review and consensus statement on behalf of the Italian Society of Infectious Diseases and International Society of Chemotherapy

Skin and soft-tissue infections (SSTIs) are among the most common bacterial infections, posing considerable diagnostic and therapeutic challenges and resulting in significant morbidity and mortality among patients as well as increased healthcare costs. eight members of the SSTI working group of the Italian Society of infectious Diseases prepared a draft of the statements, grading the quality of each piece of evidence after a careful review of the current literature using MEDLINE database and their own clinical experience. Statements were graded for their strength and quality using a system based on the one adopted by the Infectious Diseases Society of America (IDSA). The manuscript was successively reviewed by seven members of the SSTI working group of the international Society of Chemotherapy, and ultimately re-formulated by all e xperts. the microbiological and clinical aspects together with diagnostic features were considered for uncomplicated and complicated SSTIs. Antimicrobial therapy was considered as well -both empirical and targeted to methicillin-resistant Staphylococcus aureus (MRSA) and/or other main pathogens.

Italian guidelines for diagnosis, prevention, and treatment of invasive fungal infections in solid organ transplant recipients

Use of various induction regimens, of novel immunosuppressive agents, and of newer prophylactic strategies continues to change the pattern of infections among solid organ transplant (SOT) recipients. Although invasive fungal infections (IFIs) occur at a lower incidence than bacterial and viral infections in this population, they remain a major cause of morbidity and mortality worldwide. In March 2008, a panel of Italian experts on fungal infections and organ transplantation convened in Castel Gandolfo (Rome) to develop consensus guidelines for the diagnosis, prevention, and treatment of IFIs among SOT recipients. We discussed the definitions, microbiological and radiological diagnoses, prophylaxis, empirical treatment, and therapy of established disease. Throughout the consensus document, recommendations as clinical guidelines were rated according to the standard scoring system of the Infectious Diseases Society of America and the United Stated Public Health Service.

[Management and prevention of catheter-associated urinary tract infections: current opinions and clinical practice]

Catheter-associated urinary tract infection (CA-UTI) is an important epidemiological event in the hospital setting as urethral catheterization has a profound impact in terms of local and systemic extension, mortality rate, prolonged length of stay and costs, other than representing a reservoir of multi-resistant bacterial pathogens. All these issues make it mandatory to set up effective prevention measures. Any initiative able to prevent or reduce incidence of catheter-associated UTI and possible complications should be encouraged. In this context, an important role could be played by innovative catheters coated with noble metal alloy and hydrogel. Results from this consensus may prove useful as a guide for the management and prevention of CA-UTIs in Italy and elsewhere, and may also provide a basis for comparison with other studies.

Antimicrobial treatment of "complicated" intra-abdominal infections and the new IDSA guidelines ? a commentary and an alternative European approach according to clinical definitions

Recently, an update of the IDSA guidelines for the treatment of complicated intraabdominal infections has been published. No guideline can cater for all variations in ecology, antimicrobial resistance patterns, patient characteristics and presentation, health care and reimbursement systems in many different countries. In the short time the IDSA guidelines have been available, a number of practical clinical issues have been raised by physicians regarding interpretation of the guidelines. The main debatable issues of the new IDSA guidelines are described as follows: The authors of the IDSA guidelines present recommendations for the following subgroups of "complicated" IAI: community-acquired intra-abdominal infections of mild-to-moderate and high severity and health care-associated intra-abdominal infections (no general treatment recommendations, only information about antimicrobial therapy of specific resistant bacterial isolates). From a clinical point of view, "complicated" IAI are better differentiated into primary, secondary (community-acquired and postoperative) and tertiary peritonitis. Those are the clinical presentations of IAI as seen in the emergency room, the general ward and on ICU. Future antibiotic treatment studies of IAI would be more clinically relevant if they included patients in studies for the efficacy and safety of antibiotics for the treatment of the above mentioned forms of IAI, rather than conducting studies based on the vague term "complicated" intra-abdominal infections. - The new IDSA guidelines for the treatment of resistant bacteria fail to mention many of new available drugs, although clinical data for the treatment of "complicated IAI" with new substances exist. Furthermore, treatment recommendations for cIAI caused by VRE are not included. This group of diseases comprises enough patients (i.e. the entire group of postoperative and tertiary peritonitis, recurrent interventions in bile duct surgery or necrotizing pancreatitis) to provide specific recommendations for such antimicrobial treatment. - A panel of European colleagues from surgery, intensive care, clinical microbiology and infectious diseases has developed recommendations based on the above mentioned clinical entities with the aim of providing clear therapeutic recommendations for specific clinical diagnoses. An individual patient-centered approach for this very important group of diseases with a substantial morbidity and mortality is essential for optimal antimicrobial treatment.

Caspofungin for post solid organ transplant invasive fungal disease: results of a retrospective observational study

M. Winkler, J. Pratschke, U. Schulz, S. Zheng, M. Zhang, W. Li, M. Lu, D. Sgarabotto, G. Sganga, P. Kaskel, S. Chandwani, L. Ma, J. Petrovic, M. Shivaprakash. Caspofungin for post solid organ transplant invasive fungal disease: results of a retrospective observational study. Transpl Infect Dis 2010: 12: 230–237. All rights reserved

Clinical diagnosis of intra-abdominal infections

Abdominal sepsis results in high morbidity and mortality. Intra-abdominal infectious complications are one of the most common infectious pathologies seen in critically ill patients. Approximately 30% of patients admitted to an ICU with intra-abdominal infection succumb to their illness, and when peritonitis arises as a complication of a previous surgical procedure, or recurs during ICU admission, mortality rates exceed 50%. Thus early detection and treatment are essential to minimize patient complications.Critically ill patients are often clinically unevaluable due to distracting injuries, respiratory failure, obtundation, or other pathology. even when patients can be examined, the clinical exam is frequently unreliable and/or misleading. the diagnostic approach to identifying abdominal problems will differ, depending upon the hemodynamic stability of the patient. Patients who have low systolic blood pressures, who are pressor-dependent, may be too unstable to undergo analyses that require trips away from the ICU or emergency department. intra-abdominal pathology may be detected by ultrasound or diagnostic peritoneal lavage. When critically ill patients are stable enough to undergo some diagnostic evaluation of their abdomen, the approach is somewhat simpler. Overall, computerized tomography (CT) is the imaging modality of choice for most intra-abdominal processes. for diagnosis of intra-abdominal conditions using CT scanning it is optimal if patients receive both oral and intravenous contrast. An exception to the use of CT scanning is evaluation of suspected biliary pathology, which is best imaged by ultrasound. it will identify calculous and acalculous cholecystitis and may show changes in the gallbladder or common bile duct associated with biliary obstruction.

Definition and classification of intra-abdominal infections

Intra-abdominal infections represent a wide variety of pathological conditions that involve lesions of all the intra-abdominal organs. They include both inflammation of single organs and any sort of peritonitis (primary, secondary, tertiary), where the severity of the disease often depends on the extension of the inflammation (local or diffuse peritonitis). They also include intraperitoneal, retroperitoneal and parenchymal abscesses. the aim of this article is to analyze the current definitions and classifications of intra-abdominal infections.

[Antibiotic treatment of intra-abdominal and post-surgical infections]

During the last years we observed a significant decrease of the mortality following the intra-abdominal infections thanks the improvement of surgical techniques and because of the improved approach of antibiotic treatments. The antibiotic therapy for the treatment of intra-abdominal infections greatly varies according to the infection severity. It is, in fact, possible to distinguish the intra-abdominal infections in three different categories. Mild infections should be treated promptly with surgical drainage and a short term therapy with a wide range antibiotic including anaerobes (ampicillin/sulbactam, cefoxitin). Mild-moderate infections which are largely the most frequent in the clinical practice should be also treated with a single drug which include anaerobes in its spectrum. Finally severe infections require a more aggressive therapeutic approach with a combination treatment covering anaerobes (clyndamicin, metronidazole), Gram negative rods (ciprofloxacin, aminoglycosides) and Gram positive cocci (penicillins, cephalosporins) including MRSA (glycopetides) and/or VRE (linezolid). By the surgical point of view the control of intra-abdominal infections can require different procedures such as laparatomy, relaparotomy or less frequently laparostomy (totally or partially open abdomen). A strong synergy between the surgical procedures and antibiotic therapy represents the best way to approach and resolve even the most severe intra-abdominal infections.

Prediction of 6-month survival after liver transplantation using Cox regression

BACKGROUND

The outcome of liver transplantation (LTx) has been correlated with several donor and recipient factors.

METHODS

A database of 191 consecutive LTx cases was analyzed using Kaplan-Meier and Cox regression statistics based on 80 variables. To avoid additional effects of late events on patient survival, the chosen endpoint was 6 months. Data were evaluated using SPSS statistical software.

RESULTS

Kaplan-Meier analysis revealed a difference in 1- to 6-month graft survival between patients transplanted with organs from donors older versus younger than 60 years (Breslow, P <.01). Differences in 1- to 6-month graft survivals were observed between patients listed as UNOS status 3, 2B, 2A, and 1: the outcomes for UNOS status 2B versus UNOS status 2A and UNOS status 2B versus status 1 were significant (P <.05). Differences in 1- to 6-month graft survival rates were found between patients with versus without sepsis (P <.05), and with versus without rejection episodes (P <.01). Cox regression analysis revealed only three of the variables to be independent prognostic predictors of graft failure: donor age; postoperative septic status; and rejection. The best mathematical multivariate Cox regression model linked donor age + donor Na + rejection + sepsis to 1- to 6-month graft survival (chi-square = 29.06, P <.001).

CONCLUSION

Factors predictive of 1- to 6-month graft survival after liver transplantation include donor age; UNOS status; sepsis; and rejection.

Botulinum neurotoxin and other treatments for fissure-in-ano and pelvic floor disorders

BACKGROUND

The management of disorders of the lower gastrointestinal tract, such as chronic anal fissure and pelvic floor dysfunction, has undergone re-evaluation recently. To a large extent this is due to the advent of neurochemical treatments, such as botulinum neurotoxin injections and topical nitrate ointment.

METHODS AND RESULTS

This review presents, inter alia, current data on the use of botulinum neurotoxin to treat lower gastrointestinal tract diseases, such as chronic anal fissure for which it promotes healing and symptom relief in up to 70 per cent of cases. This agent has also been used selectively to weaken the external anal sphincter and puborectalis muscle in constipation and in Parkinson's disease. Symptomatic improvement can also be induced in anterior rectocele by botulinum neurotoxin injections.

CONCLUSION

Botulinum neurotoxin appears to be a safe therapy for anal fissure. It is more efficacious than nitrate application and does not require patient compliance to complete treatment. While it may also be a promising approach for the treatment of chronic constipation due to pelvic floor dysfunction, further investigation of its efficacy and safety in this role is needed before general usage can be advocated.

New perspectives in antibiotic prophylaxis for intra-abdominal surgery

Effective management of intra-abdominal infections requires a combination of preoperative preparation, antibiotic prophylaxis and appropriate surgical technique. Antibacterial prophylaxis should provide coverage of all likely pathogens, including aerobic and anaerobic organisms. Whereas antibacterial combination therapy is appropriate in certain situations, single-agent prophylaxis is appropriate for the majority of patients and ampicillin/sulbactam, with its broad-spectrum anti-aerobic/anti-anaerobic activity, is an attractive prophylactic option. Surgery involving the gastrointestinal tract provides a special challenge by virtue of its high, predominantly anaerobic, bacterial load. However, the requirement for prophylaxis varies depending upon the precise site of intervention. Biliary tract surgery requires prophylaxis in high-risk patients only, whereas hepatobiliary or pancreatic surgery requires prophylaxis in all patients. Gastroduodenal operations require prophylaxis in the presence of risk factors, such as abnormal gastric acidity or bleeding. Colorectal procedures present a high risk of anaerobic infection and sepsis, and require adequate prophylaxis combined with a thorough preoperative preparation designed to reduce considerably the bacterial load of the bowel. Where peritonitis does follow intra-abdominal surgery, patients should receive antibacterial therapy commensurate with the risk of serious infection. A small proportion of patients will be at risk of severe infection and will require triple-agent therapy. However, most patients are likely to develop mild-to-moderate infections only and can be treated with a single, broad-spectrum antibiotic agent, such as ampicillin/sulbactam, a beta-lactam/beta-lactamase inhibitor.

Anterior rectocele due to obstructed defecation relieved by botulinum toxin

Background. Surgical repair of rectocele does not always alleviate symptoms related to difficulty in defecation, and some patients have impaired fecal continence after surgical treatment. To avoid complications of surgical repair, we investigated the efficacy of botulinum toxin in treating patients with symptomatic rectocele. Methods. Fourteen female patients with anterior rectocele were included in the study. The patients were studied by using anorectal manometry and defecography, and then treated with a total of 30 units of type A botulinum toxin, injected into 3 sites, 2 on either side of the puborectalis muscle and the third anteriorly in the external anal sphincter, under ultrasonographic guidance. Results. After 2 months, symptomatic improvement was noted in 9 patients (P =.0003). At the same time, rectocele depth (mean +/- SD) was reduced from 4.3 +/- 0.6 cm to 1.8 +/- 0.5 cm (P =.0000001) and rectocele area from 9.2 +/- 1.3 cm(2) to 2.8 +/- 1.6 cm(2) (P =.0000001). Anorectal manometry demonstrated decreased tone during straining from 70 +/- 28 mm Hg at baseline to 41 +/- 19 mm Hg at 1 month (P =.003) and to 41 +/- 22 mm Hg at 2 months (P =.005). No permanent complications were observed in any patient for a mean follow-up period of 18 +/- 4 months. At 1 year evaluation, incomplete or digitally assisted rectal voiding was not reported by any patient, and a rectocele was not found at physical examination. Four recurrent, asymptomatic rectoceles were noted at defecography. Conclusions. Botulinum toxin injections should be considered as a simple therapeutic approach in patients with anterior rectocele. The treatment is safe and less expensive than surgical repair. A more precise method of toxin injections under transrectal ultrasonography accounts for the high success rate. Repeated injections may be necessary to maintain the clinical improvement.

Immunological surrogate parameters in a prognostic model for multi-organ failure and death

OBJECTIVE

To assess the ability of clinical or biochemical parameters to predict outcome (survival or non-survival; severe or moderate/no complication) using multiple regression analyses.

DESIGN

Prospective, descriptive cohort study with no interventions

SETTING

12 surgical intensive care units of university hospitals and large community hospitals; four medical school research laboratories in eight European countries

PATIENTS

128 surgical patients with major intra-abdominal surgery admitted for at least two days to an intensive care unit

MAIN OUTCOME MEASURES

Prediction of complications or survival based on analysis of clinical (Multiple Organ Dysfunction Score, Multi-Organ-Failure Score, Acute Physiology and Chronic Health Evaluation II scores) and immunological (plasma levels of endotoxin, endotoxin neutralizing capacity, IL-6, IL-8, cell associated IL-8, Fc-receptor polymorphism, soluble CD-14) parameters, with comparison of predicted and actual outcomes.

RESULTS

APACHE II, MODS score, MOF score, platelets, IL-6, IL-8, ENC, cell ass. IL-8 were significantly different between survivors and non-survivors and patients with/without severe complications by univariate analysis. By multivariate analysis only MOF, MODS score, IL-6, platelets, comorbidity predicted complications with a sensitivity of 82% and a specificity of 87%. Multivariate analysis demonstrated that only APACHE II score, plasma IL-8 and complications predicted death (sensitivity 84%; specificity 90%).

CONCLUSION

Immunological surrogate parameters may predict complications and death of surgical ICU patients. The use of several parameters may add to increase sensitivity and specificity in a prognostic model.

Extensive resection in pancreatic cancer: review of the literature and personal experience

BACKGROUND/AIMS

The surgical treatment of pancreatic carcinoma, and particularly the decision to resect locally advanced non-metastatic cancer is extremely controversial. The aim of this study is to report our experience in extensive pancreatectomy and draw conclusions regarding its effectiveness in treating locally advanced pancreatic cancer.

METHODOLOGY

In our Department of Surgery, 12 patients underwent pancreatic resective surgery extended to the portal vein (6 cases), to the superior mesenteric vein (1 case) or to other peripancreatic organs (5 cases).

RESULTS

The procedure was considered curative in 7 cases. The mortality rate was 16.6% and the morbidity 25%. Four out of the five patients who had undergone vascular resection and had not died in the postoperative period survived for more than 12 months, while the 5 cases in whom the resection was extended to other organs survived from 9 to 93 months. In all cases, the quality of life was satisfactory until tumor recurrence, which occurred in 8 cases (66.7%). Two of the cases with vascular resection are still alive after 17 and 22 months.

CONCLUSIONS

In all of these 12 cases, we were forced to perform "extensive" resective surgery, which was apparently curative, although we were not able to prevent recurrence in a high percentage of cases. Moreover, aggressive surgery seems justified in particular histotypes, such as in the carcinoid case reported in our study; debulking enhances the effectiveness of chemotherapy and permits relief of the endocrine symptoms eventually induced by the tumor.

Epidemiology, diagnosis and treatment of systemic Candida infection in surgical patients under intensive care

The incidence of systemic Candida infections in patients requiring intensive care has increased substantially in recent years as a result of a combination of factors. More patients with severe underlying disease or immunosuppression from anti-neoplastic or anti-rejection chemotherapy and at risk from fungal infection are now admitted to the ICU. Improvements in supportive medical and surgical care have led to many patients who would previously have died as a result of trauma or disease surviving to receive intensive care. Moreover, some therapeutic interventions used in the ICU, most notably broad-spectrum antibiotics and intravascular catheters, are also associated with increased risks of candidiasis. Systemic Candida infections are associated with a high morbidity and mortality, but remain difficult to diagnose and ICU staff need to be acutely aware of this often insidious pathogen. A number of studies have identified risk factors for systemic Candida infection which may be used to identify those at highest risk. Such patients may be potential candidates for early, presumptive therapy. Here we review the epidemiology, pathogenesis, morbidity and mortality of systemic Candida infections in the ICU setting, and examine predisposing risk factors. Antifungal treatment, including the use of amphotericin B, flucytosine and fluconazole, and the roles of early presumptive therapy and prophylaxis, is also reviewed.

Truncal vagotomy, antrectomy and Roux-en-Y gastrojejunostomy in the treatment of duodenogastric reflux disease

BACKGROUND/AIMS

The surgical treatment of duodenogastric reflux (DGR), resistant to medical therapy, in patients with intact stomach is difficult to standardize. The aim of this study is to present our experience on 5 patients, all cholecystectomized, with severe DGR disease treated surgically.

METHODS

Out of a group of 223 patients suffering from nonulcerous dispeptic pathology presenting to our department, we selected 5 patients suffering from alkaline reflux gastritis in intact stomach. The diagnosis of primary DGR was made using Wilson's criteria. The surgical procedure adopted consisted of a truncal vagotomy, antrectomy, and a Roux-en-Y gastrojejunostomy.

RESULTS

No perioperative mortality was observed. Twelve months after surgery all patients expressed satisfaction with the result of the operation and complained of no severe disturbances. A sense of postprandial fullness with a sense of pain in the left shoulder persisted in one case only, requiring the consumption of small and frequent meals. Radiological examination of the upper gastrointestinal tract of these patients showed notably delayed emptying of the gastric stump, while the endoscopic picture was completely normal.

CONCLUSION

The antrectomy and Roux-en-Y gastrojejunostomy is a better known operation, easily executed, and has the advantage that it can be performed on patients previously operated on for gastric resection and therefore suffering from secondary reflux. It also has the advantage of removing the gastric antrum where mucous atrophy is more frequent and is susceptible to neoplastic degeneration. However, at the present time the choice between different types of operation depends exclusively on the personal conviction and experience of the surgeon.

Modified Hill operation vs. Nissen fundoplication in the surgical treatment of gastro-esophageal reflux disease

BACKGROUND/AIMS

The authors compared the results of the Nissen fundoplication technique with the results of the Hill procedure, by using a 10-year history of patients with gastro-esophageal reflux disease.

MATERIALS AND METHODS

Seventy two consecutive patients entered the study, 32 of whom underwent a 360 degrees fundoplication according to Nissen and 40 with a modified Hill operation. In the Nissen Group, intraoperative manometry (IOM) was carried out in all patients; in the Hill Group, the patients were randomized in two sub-groups (A and B), before operation; in 20 of them (group A), the procedure was randomly associated to IOM.

RESULTS

The overall complications were low in both groups (15.6% in the Nissen Group and 5% in the Hill Group, p = 0.1), and there was no mortality rate. The clinical results were excellent or good in 28 patients (87.6%) of the Nissen Group and in 36 patients (90%) of the Hill Group (p = 0.5); in particular, an excellent outcome was observed in 16 patients (80%) with IOM (sub-group A), while 12 patients (60%) without it (sub-group B) showed similar results. The manometric studies carried out six months after surgical treatment showed a decrease of the lower esophageal sphincter pressures in all patients if compared to the pressure recorded intra-operatively. In comparison to the pre-operative values, both the lower esophageal sphincter length and its intra-abdominal portion were markedly increased in the Nissen Group and in the sub-group A of the Hill patients.

CONCLUSIONS

These results support the conclusions that modified posterior gastropexy and 360 degrees fundoplication are effective, well tolerated, and can be properly used in the treatment of Gastro-esophageal reflux disease (GERD), since both techniques showed good clinical results. A favorable clinical outcome depends mostly on adequate lower esophageal sphincter length (LESL) and LESIA extension, which could be more efficiently achieved by the use of intraoperative manometry (IOM).

Retroperitoneal laparostomy as an effective emergency treatment of abscess and multiple organ failure after blunt duodenal trauma: report of a case

Retroperitoneal abscess with multiple organ failure, after traumatic duodenal rupture followed by dehiscence of duodenal sutures, is a condition associated with a very high mortality. We report on a case treated by retroperitoneal laparostomy, a technique proposed as treatment for pancreatic abscess after an acute necrotizing pancreatitis. The retroperitoneal laparostomy creates a wide open cavity in a gravity-favorable position, allowing drainage and daily debridement of necrotic collections.

Kinetics of medium-chain triglycerides and free fatty acids in healthy volunteers and surgically stressed patients

To determine the hydrolysis rate of medium-chain triglycerides (MCTs) to medium-chain free fatty acids (MCFAs) and the disposition rate of MCFAs, five healthy volunteers (H) and eight surgically stressed patients (S) received 0.5 mL of Lipofundin 20% per kilogram body weight as an intravenous bolus. Serum MCTs (C8 and C10) and MCFAs were measured by high-performance liquid chromatography during the 120 minutes postinjection. A linear two-compartment model was found to be descriptive and robust: the apparent volumes of distribution were found to be similar in healthy and surgical subjects for both MCTs and MCFAs. The first-order transformation rate constant (hydrolysis) from MCTs to MCFAs was not significantly different between the H and S groups (overall 0.112 +/- 0.022/min, C8; 0.078 +/- 0.020/min, C10). The rate constant for tissue MCFA uptake from plasma was significantly different between S and H subjects both for C10 alone (H: 0.0337 +/- 0.0078; S: 0.1194 +/- 0.0240; p = .020) and for C8 and C10 together (H: 0.0382 +/- 0.0054; S: 0.1012 +/- 0.0168; p = .008), whereas it failed to attain significance when C8 alone was considered (H: 0.047 +/- 0.0077; S: 0.0829 +/- 0.0230; p = .210). These results show that use of MCTs is increased in surgical patients because of enhanced tissue uptake of the corresponding free fatty acids, whereas there does not seem to be an increase of MCT hydrolysis in response to acute disease. This would indicate that the stressed patient is in fact able to effectively use this alternative lipid substrate in the face of increased metabolic demand.

PC-based differential model fitting as a support for clinical research

A PC-based minimisation software written in C-language is described, which solves numerically both simple non-linear regression problems and problems expressed as systems of (unsolved) initial-value ordinary or partial differential equations. The software uses second-order iterated Runge-Kutta algorithm to approximate numerically the solution curves. It uses a quasi-Newton algorithm to minimize either sums of squares (weighted or unweighted) or NONMEM loss functions. Inverse Hessian approximation to the parameter dispersion and Monte Carlo generation of artificial samples are offered to test the robustness of the parameter values obtained. A real test problem is described, involving the hydrolysation of plasma Medium Chain Triglycerides to Free Fatty Acids and the uptake of these from plasma. Two competing models were evaluated, one involving linear terms for each transfer and one involving carrier-mediated, rate-limited hydrolysis and tissue absorption steps. The simpler linear model was found to be more robust and eventually used to describe the experimental data.

Probability and the patient state space

This paper describes work to develop a model-based system to support clinical decision-making. In previous articles, we have developed (from 695 measurement sets obtained from 148 patients) a physiologic state classification based on a set of 11 cardiovascular and metabolic measurements. There is an R or reference state, for stable ICU patients. Patients under (operative, traumatic, or compensated septic) stress, or with (septic or hepatic) metabolic, respiratory, or cardiac insufficiency are in the A, B, C, or D states, respectively. We wished to make the state easier to measure and eventually available continuously, automatically, and noninvasively, as well as reflecting a wider group of bodily systems. The 5 centers define a 4 dimensional affine subspace, designated the cardiovascular state space. Using eigenvector analysis, we have found four new derived physiologic variables CV1, CV2, CV3, and CV4 that span the state space. We have fit sets of linear regression equations that allow the patient's position in the state space, and therefore his state, to be determined from more easily obtainable sets of measurements. Further, we selected 1966 measurement sets from 512 patients at two hospitals. We used the data from 250 of these patients to define 13 prototypical types, namely survivors and deaths from various combinations of sepsis, cardiogenic decompensation, cirrhosis, and pneumonitis, following trauma or general surgery. For any future patient, the statistical theory of Bayesian inference allows one to infer back from the measurements observed to the probability of his being of any of these types and of surviving or dying. We used this method to predict the outcome of the other 262 patients, prospectively. Statistically, the predictions of survival or death were not significantly different from the actual. For individual patients, the method predicts a clinical course that closely follows the actual episodes in their history. These results confirm and explain the validity of the concept of the patient state and make the state easier to compute. The patient state and the probability plot together help to stage, select, and evaluate therapy. They do not replace the clinician's judgement, but rather are tools that help the clinician to exercise judgement.

Determinants of urea nitrogen production in sepsis. Muscle catabolism, total parenteral nutrition, and hepatic clearance of amino acids

The major determinants of urea production were investigated in 26 patients with multiple trauma (300 studies). The body clearances (CLRs) of ten amino acids (AAs) were estimated as a ratio of muscle-released AAs plus total parenteral nutrition-infused AAs to their extracellular pool. While clinically septic trauma (ST) patients without multiple-organ failure syndrome (MOFS) had a higher level of urea nitrogen production (25.6 +/- 13.4 g of N per day) compared with nonseptic trauma (NST) patients (14 +/- 7.5 g of N per day) and with ST patients with MOFS (4.28 +/- 1.5 g of N per day), in all groups urea N production was found to be a function of muscle protein degradation (catabolism), total parenteral nutrition-administered AAs, and the ratio between leucine CLR and tyrosine CLR (L/T) (r2 = .82, P less than .0001). Since tyrosine is cleared almost exclusively by the liver, the L/T ratio may be regarded as an index of hepatic function. The significant differences between urea N production in ST and NST patients lay in an increased positive dependence on muscle catabolism and increased negative correlation with L/T in the ST group. At any L/T ratio, urea N production was increased in ST patients over NST patients, but in ST patients with MOFS, it fell to or below levels of NST patients. These data show that the ST process is associated with enhancement of ureagenesis, due to increased hepatic CLR of both exogenous and endogenous AAs. In sepsis with MOFS, a marked inhibition of urea synthesis occurs, partially explained by a decreased hepatic CLR of non-branched-chain AAs.