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R enin angiotensin system (RAS) antagonists, angiotensin-converting enzyme (ACE) inhibitors, and angiotensin II receptor antagonists are increasingly used to treat cardiovascular and other diseases (1–6). These treatments induce a blockade of the RAS that may affect hemodynamics during anesthesia and surgery. In 1978, Miller et al. (7) reported that the RAS is involved in maintaining normal blood pressure during anesthesia. Although anesthesia is not invariably associated with a deleterious hemodynamic event in RAS-blocked patients (8–10), hemodynamic instability, described as unexpected episodes of hypotension, have been reported (11–13). Otherwise, stresses such as surgery or hypotension stimulate the generation of angiotensin II, which induces vasoconstriction (14) to maintain blood pressure but reduces blood flow to organs such as the kidneys and bowels. Accordingly, an angiotensin II-induced reduction in blood flow may contribute to acute renal failure (15) and splanchnic ischemia (16), which are obvious factors in postoperative morbidity (17). RAS blockade with ACE inhibitors decreases some consequences of the stress response on the regional circulation (9,18,19), which may then contribute to body protection. Much of the information regarding the physiology and pathophysiology of the RAS during anesthesia and surgery is based on the effects of ACE inhibitors. Because ACE inhibitors probably act mostly by blocking the RAS, similar effects should be obtained from angiotensin (AT) receptor antagonists. RAS antagonist pharmacology may help us to understand the hemodynamic risk of anesthesia in RAS-blocked patients, to identify predisposing factors, and to determine the potential benefit of RAS antagonists during anesthesia and surgery. Physiology of the RAS Generation of Angiotensin II

In this prospective, nonblind study, we report the use of clonidine during orthotopic liver transplantation (OLT). Twenty adult patients in a stable medical condition were studied. General anesthesia consisted of isoflurane in air/oxygen and sufentanil. Patients in the clonidine group received a slow i.v. infusion (15 min) of 4 microg/kg clonidine during induction. The other patients were used as controls. I.v. fluid requirements were determined as follows: albumin (4% solution) was administered to maintain filling pressures to a pulmonary capillary wedge pressure (PCWP) of more than 12 mm Hg. Packed red blood cells were transfused to maintain a hemoglobin level of 8-9 g/dL. Circulatory stability was evaluated using: systolic and diastolic arterial blood pressure and heart rate recorded at 2-min intervals; and the vasopressor/inotropic support required to maintain adequate hemodynamic variables after reperfusion. Intraoperative albumin and packed red blood cell requirements were significantly reduced in patients in the clonidine group (1644 +/- 140 and 50 +/- 50 mL vs 2867 +/- 226 mL and 1350 +/- 443 mL; P < 0.05). Heart rate was significantly slower in patients of the clonidine group. There were no differences in systolic arterial blood pressure. After reperfusion, patients in the control group showed significantly lower diastolic arterial blood pressure, required more vasopressor/inotropic support, and were more acidotic than patients in the clonidine group. We conclude that the administration of 4 microg/kg clonidine during induction of OLT significantly reduced the intraoperative requirements of i.v. fluids and blood products without compromising circulatory stability. Improvement in immediate reperfusion-induced disturbances was observed. IMPLICATIONS: The administration of 4 microg/kg clonidine during induction of liver transplantation significantly reduced the intraoperative requirements for i.v. fluids and blood products without compromising the circulatory stability. Improvement in immediate reperfusion-induced disturbances was also observed.

We reviewed the records of 200 children who underwent 238 orthotopic liver transplantations in order to determine which preoperative factors could predict intraoperative blood loss. A coagulation abnormality score (CAS) was calculated by allowing one point for each abnormality in six preoperative coagulation tests. The mean CAS values were significantly greater in children suffering from fulminant hepatic failure (Fulm) or post-necrotic cirrhosis (PNC) and those having retransplantation (ReTx) than in those with disease of other etiologies. No correlation was found between the CAS and the mean blood requirements in the different etiology groups. According to the amount of blood transfused, children could be divided in two groups. Group 1 were those with biliary atresia and ReTx, who received more than 200 ml/kg. Group 2 included those with PNC, Fulm, metabolic diseases, and Alagille syndrome and Byler disease, who received less than 140 ml/kg. The mean CAS was significantly lower and the PT significantly better in Group 1. We conclude that preoperative coagulation tests were weak predictors of intraoperative bleeding. The etiology of the underlying liver disease and previous abdominal surgery play an important role in the occurrence of severe bleeding. Intraoperatively, children presented the same hemostatic changes as adults.

BACKGROUND: The original method of liver transplantation (LT) included recipient inferior vena cava (IVC) resection and the use of extracorporeal venovenous bypass (VVB). Refinements in technique permit transplantation to be done with IVC preservation and without VVB use. MATERIAL AND METHODS: Between November 1993 and November 2000, 202 consecutive grafts were performed in 188 adults (>/=16 years of age). Twelve patients (6.4%) received two and three retransplants (re-LT). Split grafting was performed 19 times (19 of 202 grafts, 9.4%). Risk factors included United Network of Organ Sharing status I (n=30, 16%), previous right upper abdominal surgery (n=32, 17.1%), caudate lobe encirclement of IVC (n=65, 32.2%), IVC (n=24, 11.9%), and splanchnic venous modification (n=58, 30.9%), transjugular intrahepatic portosystemic stent shunt (n=34, 16.8%), giant (>5 kg) liver tumor (n=6, 3%), septic necrosis of the caudate lobe (n=1, 0.5%), and previous cavocaval (n=13, 6.4%) or classical LT (n=5, 2.5%). RESULTS: IVC preservation, avoidance of IVC cross clamping and of VVB use were possible in 98.9%, 93%, and 99.5% of 183 primary LT and in 89.5%, 84.2%, and 89.5% of 19 re-LT. Temporary portocaval shunting was never applied. Perioperative mortality was 1.2%. There was no allotransfusion in 73 (36%) grafts and 45 (22%) patients were immediately extubated. Permanent hepatic vein and caval problems were encountered in three (1.5%) grafts. One patient needed stent placement to treat IVC stenosis. Actual 3- and 12-month patient survival for whole, re-LT, and right-lobe split LT groups were 94.7%, 94.1%, 94.7%, 88.2%, 94.1%, and 89%. Three-month graft survival rates for these groups were 92.6%, 94.7%, and 84.2%. CONCLUSIONS: LT with IVC preservation and without VVB use and portocaval shunting is possible in nearly all primary transplants and in the majority of re-LT.

In this study we evaluated the analgesic efficacy of combined deep and superficial cervical plexus block in patients undergoing thyroidectomy under general anesthesia. For this purpose, 39 patients undergoing elective thyroid surgery were randomized to receive a bilateral combined deep and superficial cervical block (14 mL per side) with saline (Group 1; n = 13), ropivacaine 0.5% (Group 2; n = 13), or ropivacaine 0.5% plus clonidine 7.5 microg/mL (Group 3; n = 13). Deep cervical plexus block was performed with a single injection (8 mL) at the C3 level. Superficial cervical plexus block consisted of a subcutaneous injection (6 mL) behind the lateral border of the sternocleidomastoid muscle. During surgery, the number of additional alfentanil boluses was significantly reduced in Groups 2 and 3 compared with Group 1 (1.3 +/- 1.0 and 1.1 +/- 1.0 vs 2.6 +/- 1.0; P < 0.05). After surgery, the opioid and non-opioid analgesic requirements were also significantly reduced in Groups 2 and 3 (P < 0.05) during the first 24 h. Except for one patient in Group 3, who experienced transient anesthesia of the brachial plexus, no side effect was noted in any group. We conclude that combined deep and superficial cervical plexus block is an effective technique to alleviate pain during and immediately after thyroidectomy. IMPLICATIONS: Combined deep and superficial cervical plexus block is an effective technique to reduce opioid requirements during and after thyroid surgery.

Hypoxemia in cirrhotic patients is well documented. One of the possible causes of this association seems to be the presence of functional intrapulmonary shunts. The extent of the ventilation/perfusion ratio (VA/Q) abnormalities and their regression after orthotopic liver transplantation has been previously studied in adults by the multiple inert gas elimination technique. We report here a similar study in three children where the hypoxemia was the main indication for early liver grafting, although the liver function was still preserved at that time. Their hypoxemia was almost exclusively caused by a right to left shunt (VA/Q = 0) with a minimal amount of poorly ventilated but well perfused areas (Low VA/Q). This association may explain the poor response of the arterial oxygen pressure to an increased inspired oxygen concentration. Despite these very large VA/Q mismatches, the children underwent successful liver transplantations, resulting in a regression of the intrapulmonary shunt, as demonstrated by multiple inert gas elimination technique, and compatible with a normal life.

Between 1984 and 1996, the authors performed 499 liver transplants in 416 children less than 15 years old. The overall patient survival at 10 years was 76.5%. It was 71.3% for the 209 children grafted in 1984-1990; 78.5% for biliary atresia (n = 286), 87.3% for metabolic diseases (n = 59), and 72.7% for acute liver failure (n = 22). The 5-year survival was 73.6% for the 209 children grafted in 1984-1990 and 85% for the 206 grafted in 1991-1996. Scarcity of size-matched donors led to the development of innovative techniques: 174 children who electively received a reduced liver as a first graft in our center had a 5-year survival of 76% while 168 who received a full-size graft had a survival of 85% (NS). Results of the European Split Liver Registry showed 6-month graft survival similar to results obtained with full-size grafts collected by the European Liver Transplant Registry. Extensive use of these techniques allowed the mortality while waiting to be reduced from 16.5% in 1984-1990 to 10% in 1991-1992. It rose again to 17% in 1993, leading the authors to develop a program of living related liver transplantation (LRLT). The legal and ethical aspects are analyzed. Between July 1993 and October 1997, the authors performed 53 LRLTs with 90% survival. In elective cases, a detailed analysis was made of the 45 children listed for LRLT between July 1993 and March 1997 and the 79 registered on the cadaveric waiting list during the same period. Mortality while waiting was 2% and 14.5% for the LRLT and cadaveric lists, respectively. The retransplantation rate was 4.6% and 16.1% for LRLT and cadaveric transplants, respectively. Overall post-transplant survival was 88% and 82% for children who received a LRLT or a cadaveric graft, respectively. Overall survival from the date of registration was 86% and 70% (P < 0.05) for LRLT or cadaveric LT respectively. The 2-year post-transplant survival in children less than 1 year of age at transplantation was 88.8% and 80. 3% with a LRLT or cadaveric graft, respectively; patient survival after 3 months post-transplant was 95.8% and 91.9% for stable children waiting at home, 93.7% and 93.7% in children hospitalized for complications of their disease, and 89.5% and 77.7% for children hospitalized in an intensive care unit at the time of transplantation for children who received a LRLT or cadaveric graft, respectively. It is concluded that LRLT seems to be justified for multidisciplinary teams having a large experience with reduced and split liver grafting.

Seventy-five cirrhotic patients were submitted to peroperative hemodynamic investigations including flow and pressure studies. Sixty-two patients with hepatopedal portal flow underwent a therapeutic end-to-site portacaval shunt (PC) in conjunction with arterialization of the portal vein and 13 with a stagnant flow a PC shunt alone. Thirty-five patients were operated on in emergency and 40 electively. In 61 patients portal flow was correlated with maximum perfusion pressure (r=0.66), and in 33 patients with the reduction of corrected sinusoidal pressure induced by the occlusion of the portal vein (r=0.72). Operative mortality, which was 3.5% for 57 class A and B patients and 55.5% for 18 class C patients, differed significantly (p less than 0.05) in emergency between arterialized (14.8%) and nonarterialized patients (62.5%). At the time this study was ended on July 15, 1981, the follow-up was over two years for all the patients. The five-year actuarial survival rate of the arterialized patients was 48% for the whole group and 56% for class A and B patients; the overall incidence of chronic encephalopathy was 20%. It is concluded that arterialization is a safe surgical procedure that could be beneficial in respect with operative mortality in emergency, late survival, and tolerance to portacaval shunt. However, a prospective randomized study such as the one undertaken in December 1979 is the only method to prove clearly that arterialization is really able to minimize the risk of encephalopathy and to prolong the long-term survival after portacaval shunt.

The recipient's hemodynamic condition during anesthesia for renal transplantation has a major influence on the early diuresis of the graft. The effect of maximal hydration during operation was studied in a series of 120 primary human cadaver kidney transplantations performed under peroperative monitoring of the pulmonary arterial pressures (PAPs). The PAPs levels before and at the time of clamp release were correlated with the frequency of postoperative acute tubular necrosis (ATN). The 120 patients were divided in two groups according to the PAPs levels before release of the vascular clamps: group 1 (22 patients) with a mean PAP (PAP) of less than or equal to 20 mm Hg and a diastolic PAP (DPAP) of less than or equal to 15 mm Hg was compared with group 2 (98 patients) with a PAP of greater than 20 mm Hg and a DPAP of greater than 15 mm Hg. Both groups were comparable with regard to the donor's data and the quantity of peroperative fluids. The frequency of ATN was 36% in group 1 versus only 6% in group 2. This difference is attributed to the different hemodynamic conditions in both groups: at the beginning of the transplant procedure, PAP, DPAP, and central venous pressure (CVP) were higher in group 2; at the time of clamp release, PAP, DPAP, CVP, and systolic blood pressure (SBP) were also higher in group 2. This study emphasizes the importance of the PAPs levels at the time of release of vascular clamps to avoid postoperative ATN of a kidney transplant.

Thoracic duct drainage (TDD) may be of value for removing toxic substances released by the inflamed pancreas and which are responsible for lung damage. We have prospectively assessed the efficacy of TDD in improving pulmonary gas exchange in 12 patients with severe acute pancreatitis (SAP) complicated by persistent respiratory failure despite standard conservative treatment including peritoneal dialysis in 8 patients. In group A were 6 patients (mean Ranson score=7.3) with adult respiratory distress syndrome (ARDS) and in group B were 6 hypoxemic patients (mean Ranson score=6.6) judged to be at risk of developing ARDS. The duration of TDD ranged from 3 to 10 days and the total amount of drained lymph (L) varied from 770 to 15 600 ml. Immunoreactive trypsin levels were significantly higher in L when compared to blood in both groups. Leukocyte myeloperoxidases in L (normal value < than 332±82 ng/ml in plasma) were increased in 5 of 5 group A patients (830±317 ng/ml) and in 3 of 6 patients in group B (671±467 ng/ml). After TDD pulmonary gas exchange as measured by median PaO2/FiO2 (mmHg) improved from 148±60 to 285±42 in group A and from 192±37 to 330±42 in group B (p

Revue de 120 transplantations de rein de cadavre. La necrose tubulaire aigue peut etre significativement moins frequente si le receveur est dans un etat d'hydratation maximale au moment de l'operation. En l'absence de necrose tubulaire aigue les suites postoperatoires sont simplifiees et la surveillance pour deceler les signes de rejet facilitee

The early detection of peritoneal infection in certain clinical situations such as liver cirrhosis, acute pancreatitis and after surgery is still difficult [1–3]. Even after a full clinical assessment and careful inspection of the body fluid (including gram stain, complete differential blood cell count and measurement of glucose and protein levels), the diagnosis may still be in doubt. The culture represents the only reliable test but the necessary period of incubation prevents it from being a prime factor of therapeutic decision. Indeed, the cultivation of bacteria takes at least 24 to 48 h. In the mean time, administration of therapy may be delayed.

Children with Alagille's syndrome are at increased perioperative risk during orthotopic liver transplantation due to the cardiopulmonary abnormalities and the hemodynamic changes associated with this procedure. We studied 16 children with Alagille's syndrome who underwent 21 orthotopic liver transplantations. Peripheral pulmonary stenosis was present in all subjects. Right ventricular pressures were increased in 15 cases. Caval clamping resulted in a mean decrease of 15 +/-9 mm Hg in systolic blood pressure, 5 +/- 3 mm Hg in mean pulmonary artery pressure, and 4 +/- 3 mm Hg in central venous pressure. Systolic blood pressure decreased by 16 +/- 13 mm Hg, whereas mean pulmonary artery pressure and central venous pressure increased by 3 +/- 4 mm Hg and 1 +/- 4 mm Hg, respectively, at portal vein unclamping. There was no correlation between severity of pulmonary artery stenosis and hemodynamic changes. Veno-venous bypass used in four cases resulted in smaller hemodynamic changes. Time to extubation and duration of intensive care unit stay were unrelated to severity of pulmonary artery stenosis. IMPLICATIONS: Some children with Alagille's syndrome require liver transplantation. In our study, associated pulmonary artery stenosis did not dramatically increase perioperative risk. Veno-venous bypass decreased intraoperative hemodynamic changes in these patients.

This experimental study in dogs was designed to investigate whether maximal loading produces atrial natriuretic factor (ANF) release and whether this physiological peptide is involved in the improvement of the early renal function recovery after acute ischemia. The experimental protocol included a renal artery occlusion for 45 min in uninephrectomized dogs and the measurement of various parameters of renal function over 2-hr period after declamping. There were 3 experimental groups. In the control group (I) (n = 10), the dogs received, after ischemia, an isotonic saline solution infusion at a rate of 0.2 ml/kg/min. In group II, (n = 10) the animals underwent acute volemic expansion (1 ml/kg/min) with whole blood (hematocrit approximately equal to 25%) during the ischemic period, and after declamping, an isotonic saline infusion (NaCl 0.9%) infusion at the same rate as in the control group. In group III, (n = 8) the dogs only received NaCl 0.9% (0.2 ml/kg/min) before ischemia and alpha human ANF (3.6 ng/kg/min) dissolved in saline after ischemia and during the 2 hr of the renal recovery period. Volemic expansion induced a highly significant increase of the cardiac filling pressures concomitant with a prompt but transient 5-6-fold increase in ANF levels (357 +/- 92 pg/ml versus 60 +/- 4.1 pg/ml in controls at the time of declamping [P less than 0.05]). With these higher plasma ANF levels in overloaded animals, we observed, 2 hr after declamping, considerably improved renal function recovery in terms of glomerular filtration rate--37.5% +/- 8.7 versus 11.8 +/- 3.9%; urinary sodium excretion rate--53.89 mu eq/min versus 5.36 +/- 1.2 mu eq/min (P less than 0.01); total Na reabsorption rate--1.2 +/- 0.23 meq/min versus 0.28 +/- 0.09 meq/min (P less than 0.01) (group II vs. controls, respectively). A 1-28 alpha ANF infusion after the ischemic insult allowed a comparable but more significant improved recovery of renal function--indeed, 2 hr after declamping, the GFR reached 73.7 +/- 14% of the preoperative GFR values. The urinary sodium excretion rate was 15-fold higher than in controls, and the total and fractional sodium reabsorption rates followed a similar increase. These beneficial effects of ANF were obtained with low doses of synthetic ANF (3.6 ng/kg/min) inducing plasma levels slightly higher (120 pg/ml) than in controls and comparable to the levels reached in the overloading group. In addition, maximal loading or ANF infusion produces an inhibition of the aldosterone rise occurring after the ischemic insult.(ABSTRACT TRUNCATED AT 250 WORDS)