Detrimental graft survival of size-mismatched graft for high model for end-stage liver disease recipients in liver transplantation.

BACKGROUND: In orthotopic liver transplantation (OLT) size-mismatch may cause adverse outcomes. We previously reported on a method to predict donor-recipient size-mismatch using the body surface area index (BSAi). In this study, we hypothesized that graft survival of size-mismatch transplantation deteriorates with higher model for end-stage liver disease (MELD) score at transplantation. METHODS: We evaluated non-parametrically the association of BSAi and MELD with 1-year graft survival with a generalized additive model. For derivation, transplantations performed between 2005 and 2010 were used. The associations were then validated by comparing Kaplan-Meier estimates between patient groups stratified according to estimated risk, using transplantations from 2011-2013. RESULTS: A total of 30,870 OLT were included in the study with 16,466 in the validation group. The derivation model revealed that graft survival significantly decreased with higher or lower BSAi, and with higher MELD (P < 0.0001). Validation confirmed the correlation of observed graft survival with estimated risk categories. CONCLUSIONS: We found that there is an interactive effect between MELD score and size-mismatch. Also high MELD recipient has a narrower safety margin for size-mismatched graft. The risk calculated from our nonparametric model with MELD and BSAi well predicts outcome in liver transplantation.

A randomized clinical trial testing the anti-inflammatory effects of preemptive inhaled nitric oxide in human liver transplantation.

Decreases in endothelial nitric oxide synthase derived nitric oxide (NO) production during liver transplantation promotes injury. We hypothesized that preemptive inhaled NO (iNO) would improve allograft function (primary) and reduce complications post-transplantation (secondary). Patients at two university centers (Center A and B) were randomized to receive placebo (n = 20/center) or iNO (80 ppm, n = 20/center) during the operative phase of liver transplantation. Data were analyzed at set intervals for up to 9-months post-transplantation and compared between groups. Patient characteristics and outcomes were examined with the Mann-Whitney U test, Student t-test, logistic regression, repeated measures ANOVA, and Cox proportional hazards models. Combined and site stratified analyses were performed. MELD scores were significantly higher at Center B (22.5 vs. 19.5, p<0.0001), surgical times were greater at Center B (7.7 vs. 4.5 hrs, p<0.001) and warm ischemia times were greater at Center B (95.4 vs. 69.7 min, p<0.0001). No adverse metabolic or hematologic effects from iNO occurred. iNO enhanced allograft function indexed by liver function tests (Center B, p<0.05; and p<0.03 for ALT with center data combined) and reduced complications at 9-months (Center A and B, p = 0.0062, OR = 0.15, 95% CI (0.04, 0.59)). ICU (p = 0.47) and hospital length of stay (p = 0.49) were not decreased. iNO increased concentrations of nitrate (p<0.001), nitrite (p<0.001) and nitrosylhemoglobin (p<0.001), with nitrite being postulated as a protective mechanism. Mean costs of iNO were $1,020 per transplant. iNO was safe and improved allograft function at one center and trended toward improving allograft function at the other. ClinicalTrials.gov with registry number 00582010 and the following URL:http://clinicaltrials.gov/show/NCT00582010.

Drug management in emergent liver transplantation of mitochondrial disorder carriers: review of the literature.

BACKGROUND: Mitochondrial respiratory-chain disorders (MRCD) lead to progressive disabling of neurological and cellular conditions that involve muscles, brain, kidney, and liver dysfunction. Affected individuals may need surgery, including orthotopic liver transplantation (OLT). Surgery poses anesthesia challenges because of the prolonged use of anesthetic drugs and sedatives, which may inhibit oxidative phosphorylation, mimic mitochondrial cytopathic disorders, or unveil them ex novo. MATERIALS AND METHODS: We conducted a multilingual PubMed search of surgical and non-surgical anesthesia reports between the years 1992 and 2008, where anesthetic drugs were used in MRCD patients, especially for those undergoing urgent OLTs. RESULTS: There were 51 case reports of 210 anesthesia and critical care interventions in patients with MRCD, a large part of them were children. Data pertaining to the safe usage of anesthesia and perioperative drugs were limited and conflicting. We found no article that addressed the issue of perioperative handling of urgent OLT in MRCD patients. We therefore suggest our own - although limited - experience for such occasions. CONCLUSION: There are no randomized, controlled, trial-based indications regarding safe anesthetic drugs to be used perioperatively in MRCD carriers. Consultation among geneticists, anesthesiologists, intensivists, and surgeons is essential in patients with known/suspected metabolic syndrome for planning appropriate perioperative care.

Anesthetic implications of the new anticoagulant and antiplatelet drugs.

In this review, we discuss the anesthetic implications of the new anticoagulant and antiplatelet drugs, focusing our discussion mainly on neuroaxial/regional anesthesia and central catheter placement issues. We offer practical recommendations for their use.

A multicenter evaluation of safety of early extubation in liver transplant recipients.

Small single-institutional studies performed prior to the introduction of organ allocation using the Model for End-Stage Liver Disease (MELD) suggest that early airway extubation of liver transplant recipients is a safe practice. We designed a multicenter study to examine adverse events associated with early extubation in patients selected for liver transplantation using MELD score. A total of 7 institutions extubated all patients meeting study criteria and reported adverse events that occurred within 72 hours following surgery. Adverse events were uncommon: occurring in only 7.7% of 391 patients studied. Most adverse events were pulmonary or surgically related. Pulmonary complications were usually minor, requiring only an increase in ambient oxygen concentration. The majority of surgical adverse events required additional surgery. Analysis of a limited set of perioperative variables suggest that blood transfusions and technical factors were associated with an increased risk of adverse events. In conclusion, while early extubation appears to be safe under specified circumstances, there are performance differences between institutions that remain to be explained.

Intraoperative epoprostenol and nitric oxide for severe pulmonary hypertension during orthotopic liver transplantation: a case report and review of the literature.

BACKGROUND: The presence of pulmonary hypertension in patients scheduled for liver transplantation requires a comprehensive perioperative heart evaluation and treatment with epoprostenol (prostacycline) infusion until a liver donor becomes available. We contended that intraoperative attenuation of severe pulmonary hypertension could be achieved by epoprostenol infusion combined with nitric oxide inhalation. CASE REPORT: A 49 years old man with end stage liver disease secondary to hepatitis C and ethanol abuse presented for orthotopic liver transplantation. The case was complicated by severe pulmonary hypertension. Preoperative epoprostenol, at doses ranging from 6 to 26 ng.kg(-1).min(-1), was infused during the induction of anesthesia. Although lower than before (>70 mmHg), post-induction pulmonary pressure (by Swan-Ganz catheter) was 62/30 mmHg. Prior to surgical incision nitric oxide (NO) by inhalation was commenced, increasing the concentration from 10 to 40 ppm; pulmonary artery pressure (PAP) then declined to 55/25 mmHg. Before starting reperfusion of the transplanted liver, NO concentration was increased to 80 ppm: this allowed completion of the procedure with PAP at 32/16 mmHg. Real time transesophageal echocardiography indicated improvement in right heart function due to NO. Following surgery, NO was continued for 10 hs at a concentration of 40 ppm and the patient was then extubated. Epoprostenol infusion was continued for 2 months after the patient was discharged home; last PAP was measured 32/10 mmHg. CONCLUSIONS: Severe intraoperative pulmonary hypertension during liver transplantation was successfully treated using the combination of IV epoprostenol infusion and NO inhalation in medium and high concentrations.

Adjuvant drugs for end-stage liver failure and transplantation.

End-stage liver failure is currently treatable both by dialysis and by liver transplantation, but this does not detract from its being a complex pathophysiological and pharmacological entity. More patients survive after transplant because of the impressive developments that enabled improved liver preservation, anesthesia and surgical techniques, as well as immunosuppressive drug therapy. Because of its multifaceted metabolism, liver failure can nevertheless cause a complex of pathophysiological conditions and, as such, poses a challenge for surgeons and anesthesiologists alike, not only before surgery but during transplantation as well. Obviating these problems frequently requires the use of adjunct drugs before, during and after liver transplantation, and these medications must be carefully balanced with each other while being alert to the avoidance of negative side effects. Hepatorenal syndrome and massive bleeding are the two main grave phenomena that characterize these patients before and during liver transplant, and this article will provide an overview of the adjunct drugs that are used to circumvent them perioperatively. Specifically, it details the drugs that are used to preserve and improve the already precarious hemodynamic conditions (e.g, by vasopressors, vasodilators, and beta blockers), as well as diuretics and hepato-protective drugs (e.g, furosemide, mannitol), antifibrinolytics (including the new recombinant activated Factor VII) and immunosuppressive drugs. Their doses and the ongoing debate on their concomitant use are reported as well.

Intraosseous emergency access by physicians wearing full protective gear.

OBJECTIVES: To assess prospectively and randomly the feasibility, speed, and success rate of establishing an intraosseous access using the Bone Injection Gun (BIG) while wearing antichemical outfits. METHODS: Attempts to introduce intraosseous injection with or without a full protective gear (antichemical body suit, face mask, and butyl gloves) were performed using a turkey bone model. Time to proper placement was measured. RESULTS: The average time to successfully insert the BIG's needle while wearing a protective gear was 32 +/- 3 seconds compared with 22 +/- 2 seconds (p<0.05) without the outfit. Success rate was greater than or equal to 80%. When failure occurred, a second attempt always proved successful. CONCLUSIONS: The intraosseous insertion of the BIG's needle is rapid and easy but requires 50% more time when wearing protective gear than without it. Its use during emergent treatment of toxic mass casualty is of potential benefit and needs further investigation.

Intraoperative TEE for the management of pulmonary tumour embolism during chondroblastic osteosarcoma resection.

PURPOSE: Chondroblastic osteosarcoma requiring surgical intervention is associated with a high risk of pulmonary tumour embolism. Rapid intraoperative diagnosis with transesophageal echocardiography (TEE) allowed changing the management plan and treatment of a life-threatening pathology. CLINICAL FEATURES: A 32-yr-old female with right pelvic chondrosarcoma presented for right hemipelvectomy. Two hours into the operation during ligation of the iliac blood vessels the patient's hemodynamic condition deteriorated and was followed by cardiac arrest. TEE was performed immediately and revealed massive tumour embolism in the right and left pulmonary arteries. Large tumour emboli were removed from the right and left pulmonary arteries after median sternotomy under cardiopulmonary bypass and moderate hypothermia. The hemipelvectomy was completed on the next day after fluid and inotropic agent resuscitation. An inferior vena cava filter was placed below the renal veins. The patient was discharged from hospital ten days after the surgery. CONCLUSION: This case report illustrates the important role TEE can play in the early diagnosis and subsequent surgical treatment of noncardiac emergencies. Intraoperative TEE can have a significant impact on the decision making process in life threatening emergencies.

Unexpected surgical difficulties leading to hemorrhage and gas embolus during laparoscopic donor nephrectomy: a case report.

PURPOSE: To report the case of a laparoscopic donor nephrectomy in which the preoperative evaluation of the patient gave no indication of the surgical difficulties that were encountered intraoperatively, resulting in substantial bleeding, a suspected gas embolism, and emergency conversion of the procedure from laparoscopic to open donor nephrectomy. CLINICAL FEATURES: A 59-yr-old man - height: 175 cm, weight: 85.5 kg, American Society of Anesthesiologists physical status I - presented as kidney donor for laparoscopic donor nephrectomy. He was healthy, on no medication, and had no previous abdominal surgery or diseases of the urinary tract. The preoperative computed tomography (CT) scan evaluation of his kidneys confirmed this by reporting a normal bilateral renal and renal vascular anatomy. In contradiction to the preoperative CT scan findings, the surgeon discovered abnormalities in the operative field. This included extensive scarring surrounding the left kidney, adenopathy near the right hilum, and a large branch lumbar vein entering the renal vein. The large branch lumbar vein was clipped but the clips dislodged, causing significant blood loss, and a suspected gas embolus. The procedure was converted to an emergency open donor nephrectomy. Postoperatively the patient made a full recovery. CONCLUSION: Laparoscopic donor nephrectomies, though usually performed on healthy individuals, have their pitfalls, and complications during this procedure can be sudden and serious. As shown in this case, although CT scan results are regarded as reliable, they can be misleading. As an anesthetic precaution for possible gas emboli during laparoscopic procedures, nitrous oxide should be avoided and the patient be ventilated with 100% oxygen.

Laryngeal mask anesthesia in children: a case report.

The laryngeal mask airway has become one of the major tools of modern anesthesia airway management. Despite the fact that no time limit has been recommended regarding its safe use in spontaneously breathing children, or adults, there is still reluctance to use the laryngeal mask airway in operations of long duration. We report the case of an uneventful 5-hour long laryngeal mask anesthesia in a spontaneously breathing 11-year-old boy undergoing lower limb surgery.

Preoperative fasting after soft drink intake: 2 hours may be enough.

Sufficient preoperative fasting time is essential for safe induction of anesthesia to prevent aspiration of gastric contents. However, the time recommended for sufficient preoperative fasting varies greatly, depending on the nature of the oral intake, from 2 h for clear liquids to 6 h for solid foods. We report the case of a 30-year-old man who drank about 600 ml of the carbonated, glucose-rich soft drink, 7-UP, 2 h before surgery and absorbed nearly all of it within these 2 preoperative hours.