The use of balanced HES 130/0.42 during complex cardiac surgery; effect on blood coagulation and fluid balance: a randomized controlled trial.

INTRODUCTION: Colloids and crystalloid are used during cardiac surgery for priming of the cardiopulmonary bypass (CPB) circuit. Colloids may decrease postoperative fluid balance because of their high oncotic pressure and low risk of fluid extravasation. On the other hand, colloids have been shown to impair blood coagulation. MATERIALS AND METHODS: In a prospective, randomized, double-blinded study, 50 patients scheduled for coronary artery bypass grafting or a valve procedure were planned to be randomized to receive either balanced 6% HES130/0.42 or Ringer-acetate solution for CPB priming. Randomization was stopped prematurely after 35 randomized patients (19 in the HES and 16 in the Ringer groups) because of the published report where HES130/0.42 was associated with impaired renal function. Effects on haemostasis and fluid balance were investigated. RESULTS: The rotational thromboelastometry (ROTEM®) parameters and chest tube drainage on the first postoperative morning (1POM) were comparable between the groups (p>0.05). However, patients in the HES group needed more blood and blood product transfusions. The total volume administered into the CPB circuit was lower in the HES than in the Ringer (RIN) group, 2905±1049 mL versus 3973±1207 mL (p=0.011), but there was no statistically significant difference in total fluid balance on the 1POM (5086±1660 mL in the HES group versus 5850±1514 mL in the RIN group, respectively). CONCLUSIONS: After complex cardiac surgery, the use of balanced 6% HES130/0.42 solution for CPB circuit priming did not impair haemostasis measured by ROTEM®, but it increased the need for transfusions. Fluid balance after CPB was less positive in the HES group, but, on the 1POM, it was comparable between the groups.

Pregabalin has an opioid-sparing effect in elderly patients after cardiac surgery: a randomized placebo-controlled trial.

BACKGROUND: In this prospective, randomized, double-blind, placebo-controlled study, we investigated the effect of pregabalin on oxycodone consumption, postoperative confusion, and pain in elderly cardiac surgery patients. METHODS: Seventy patients, aged ≥75 yr, were randomized to receive either 150 mg of pregabalin before operation and 75 mg of pregabalin twice daily for 5 postoperative days or placebo. Pain intensity was measured with the Verbal Rating Scale (VRS). When pain intensity was ≥2 on the VRS, patients received oxycodone either i.v. (0.05 mg kg(-1)) or orally (0.10-0.15 mg kg(-1)). Postoperative confusion was measured with the Confusion Assessment Method for the intensive care unit (CAM-ICU). Postoperative pain was assessed by a telephone interview 1 and 3 months after operation. RESULTS: Cumulative consumption of parenteral oxycodone during 16 h after extubation was reduced by 44% and total oxycodone consumption from extubation to the end of the fifth postoperative day was reduced by 48% in the pregabalin group. Time to extubation was 138 min shorter and CAM-ICU scores were significantly lower on the first postoperative day in the placebo group, although there was no significant difference with respect to the Mini-Mental State Examination or the Richmond Agitation Sedation Score. The incidence of pain during movement was significantly lower in the pregabalin group at 3 months postoperative. CONCLUSIONS: The administration of pregabalin reduced postoperative opioid consumption after cardiac surgery reduced the incidence of confusion on the first postoperative day and increased time to extubation when compared with placebo. Three months after operation, patients in the pregabalin group experienced less pain during movement.

Impact of early angiographic evaluation on the frequency of emergency reoperations after coronary bypass surgery.

BACKGROUND AND AIMS: early graft failure following coronary bypass surgery results in elevated morbidity and mortality. This study focused on the impact of angiographic graft evaluation. MATERIAL AND METHODS: of 5251 coronary artery bypass grafting (CABG) patients, 36 with postoperative persistent ischaemia underwent early angiography (23) or emergency resternotomy (13) 2000-2007 (Angiography era). Of the 23 patients, who underwent angiography, five were subsequently reoperated. Of 8807 CABG patients, 76 underwent postoperative emergency resternotomy 1988-1999 (Pre-angiography era) and served as controls. RESULTS: the angiography era patients were older (64.0 years vs. 58.2 years, P = 0.002) and the proportion of female patients (22% vs. 43%, P = 0.029) was smaller. The rate of emergency reoperations decreased (0.86% vs 0.34%, P < 0.001) during the Angiography era and graft repairs (P = 0.013) or additional grafts (P = 0.006) were less frequent, although occluded anastomoses were observed more often (P = 0.043). In 5 Angiography era patients graft complications were corrected with percutaneous coronary intervention. ICU stay (5.72 + 0.98 days vs. 5.53 + 0.68 days) and hospital stay (12.2 + 1.54 days vs. 13.1 + 1.63 days) did not differ between the groups, but the rate of myocardial infarction (63.8% vs. 92.1%, P < 0.001) and in-hospital death (22.2% vs. 46.1%, P = 0.015) decreased. CONCLUSION: after the introduction of early postoperative angiographic evaluation of CABG patients the rate of emergency reoperations and related morbidity and mortality decreased.

Hydroxyethylstarch and gelatin solutions impair blood coagulation after cardiac surgery: a prospective randomized trial.

BACKGROUND: Colloids are often used after cardiac surgery as intravascular volume replacement therapy. Cardiac surgical patients have an increased risk of bleeding. Both hydroxyethylstarch (HES) and gelatin solutions impair haemostasis. We examined the impact and dose effect on coagulation of HES 130/0.4, gelatin, or Ringer's acetate solutions after cardiac surgery. METHODS: Forty-five patients received three boluses (each 7 ml kg(-1)) of either 6% HES 130/0.4, 4% gelatin, or Ringer's acetate solution after elective cardiac surgery. The infusion of study solution was continued in the dose 7 ml kg(-1) over the following 12 h. The total dose of study solution was 28 ml kg(-1). Hypovolaemia was treated with Ringer's acetate. Modified thromboelastometry was performed to detect coagulation disorders. RESULTS: Clot formation time was prolonged and clot strength decreased after infusion of 7, 14, and 21 ml kg(-1) of either colloid compared with the Ringer's acetate group. After infusion of 14 and 21 ml kg(-1) of Ringer's acetate, clot strength was slightly, but significantly, increased. On the first postoperative morning, clot strength was still decreased in the gelatin group in comparison with the Ringer's acetate group. Neither HES nor gelatin induced fibrinolysis. Chest tube drainage was comparable between all groups. CONCLUSIONS: Even a small dose of HES 130/0.4 or gelatin impaired clot strength after cardiac surgery in a dose-dependent fashion, but neither colloid increased blood loss.

Comparison of effects and plasma concentrations of opioids between elderly and middle-aged patients after cardiac surgery.

BACKGROUND: In elderly patients, opioids may cause prominent postoperative sedation and respiratory depression. We evaluated the influence of age on the effects of opioids and plasma concentrations of fentanyl and oxycodone in cardiac surgery patients. METHODS: Thirty (>or=75 years, gender M9/F21) and 20 (

Haemodynamics and acid-base equilibrium after cardiac surgery: comparison of rapidly degradable hydroxyethyl starch solutions and albumin.

BACKGROUND: Stable haemodynamics is often achieved by administration of colloids after cardiac surgery. We conducted a prospective, randomized, open-label study comparing haemodynamics and acid-base equilibrium after infusion of two rapidly degradable hydroxyethyl starch (HES) solutions or human albumin (HA) to cardiac surgical patients. MATERIALS AND METHODS: 45 patients received a predetermined fixed dose of 15 ml kg(-1) of either 6% HES (mW 130 kDa, n = 15), 6% HES (MW 200 kDa, n = 15) or 4% HA (MW 69 kDa, n = 15) after on-pump cardiac surgery. RESULTS: Left ventricular filling pressures assessed using pulmonary artery catheter responded similarly in all groups. mean (SD) cardiac index was higher in HES130 [3.5 l min(-1) m(-2) (0.7) ] and HES200 [3.5 l min(-1) m(-2) (0.5)] than in HA [2.8 l min(-1) m(-2) (0.6)] group after completion of infusion (P = 0.002) but no differences were detected at 2 and 18 hours. Oxygen delivery increased in both HES groups but not in HA group. After cessation of infusion base excess was the most negative in Ha group. At 2 hours mean (SD) base excess was higher in HES130 [0 (1.32)] than in HES200 [-1.32 (2.27) ] and HA [-2.3 (1.3)] group (P = 0.002, between the groups). CONCLUSIONS: We conclude that the effect of albumin on cardiac performance is inferior than that of HES130 or HES200 in early postoperative phase after cardiac surgery. HES130 induces no alterations in acid-base equilibrium whereas a negative base excess was observed after HA infusion.

Applicability of tools to assess pain in elderly patients after cardiac surgery.

BACKGROUND: Post-operatively, elderly patients with impaired vision and cognitive dysfunction may experience difficulties understanding standard pain assessment tools such as the 10-cm Visual Analogue Scale (VAS) and the Verbal Rating Scale (VRS). Thus, there is a need to identify more feasible post-operative pain assessments for elderly patients. With this goal in mind, we compared the VAS and VRS with two more expressive tools: the 50-cm Red Wedge Scale (RWS) and the Facial Pain Scale (FPS). METHODS: Cardiac surgery patients (73 +/- 5 years, mean +/- SD) were allocated to an RWS (n=80) or an FPS (n=80) group. Pain was assessed at rest and after movement during the first 4 days after tracheal extubation. The RWS or FPS assessments were repeated after 10 min. All patients completed the VRS and VAS. RESULTS: The rates of successful pain measurement on study day 1 were: VRS 86%, VAS 62%, RWS 78%, and FPS 60%. Pain measurements with the RWS correlated with the VAS (r=0.758, P<0.001) and weaker with the VRS (r=0.666, P<0.001) measurements. Pain measurements with the FPS correlated well with the VAS (r=0.873, P<0.001) and weaker with the VRS (r=0.583, P<0.001) measurements. With all scales, success rates improved during the study period. CONCLUSION: In elderly patients, immediately after cardiac surgery, the VRS is the most feasible pain scale, followed by the RWS. The traditional 10-cm VAS is unsuitable for pain measurement in this population.

A comparison of the haemodynamic effects of 4% succinylated gelatin, 6% hydroxyethyl starch (200/0.5) and 4% human albumin after cardiac surgery.

BACKGROUND AND AIMS: The goal for volume replacement therapy is to maintain stable haemodynamics after cardiac surgery. We hypothesized that a short term infusion of hydroxyethyl starch results in better haemodynamic response than an infusion of lower molecular weight gelatin. MATERIAL AND METHODS: 45 patients received a predetermined fixed dose of 15 ml kg(-1) of either 4% succinylated gelatin (GEL) or 6% hydroxyethyl starch (HES) or 4% human albumin (HA) after cardiac surgery. RESULTS AND CONCLUSIONS: Pulmonary capillary wedge pressure was more increased in GEL and HES groups [mean (SD) 153% (54) and 168% (57) of pre-infusion value] than in HA group [122% (23)] (P = 0.031) after completion of infusion, but no differences in cardiac index (CI) and stroke volume index (SVI) were observed. At 2 and 18 hours after end of study infusions SVI was more increased in HES [143% (38) and 148% (41) of pre-infusion values] and HA [143% (35) and 163% (42) of pre-infusion values] groups than in GEL [116% (23) and 125% (30)] group (P = 0.047 at 2 hours and P = 0.033 at 18 hours). In early postoperative phase after cardiac surgery, HES and HA infusions improve haemodynamics more and longer period than GEL infusion.

Vasopressin, when added to norepinephrine, was not associated with increased predicted mortality after cardiac surgery.

BACKGROUND AND AIMS: Arginin vasopressin (AVP) is a potent vasoconstrictor which has been used in vasodilatory shock when therapy with catecholamines and fluids has failed. In this study we evaluated the association of AVP with organ failure and mortality in cardiac surgical patients suffering from vasodilatory shock refractory to norepinephrine (NE) treatment. MATERIAL AND METHODS: Cardiac surgical patients who received AVP in addition to NE (N=33, AVP-group) and 33 control patients (NE group) who were treated with an equal dose of NE compared with AVP patients when AVP infusion started. Data on preoperative risk factors according to EuroSCORE and predicted mortality calculated by logistic EuroSCORE were collected preoperatively. Data on hemodynamics, organ dysfunctions, length of intensive care unit stay and mortality were collected. RESULTS: EuroSCORE did not differ between the groups, AVP:10.4 +/- 3.9 vs. NE 8.9 +/- 4.0. Observed 30 day mortality was lower than predicted in both groups, AVP: 7 (21.7%) vs. predicted mortality 25.9% and NE: 2 (6.1%) vs. 16.0%, respectively. There were more renal complications (36.4% vs. 9.1%, p = 0.008) and infections (30.3% vs. 3.0%, p = 0.003) in patients receiving AVP. Cardiovascular complications did not differ between the groups. CONCLUSIONS: In this prospectively observed cohort of cardiac surgical patients, AVP did not increase mortality predicted by Euroscore. Anyhow renal and infection complications were common.

Antithrombin reduces pulmonary hypertension during reperfusion after cardiopulmonary bypass in a pig.

BACKGROUND: Antithrombin (AT) may alleviate many cardiopulmonary bypass (CPB) and ischemia-reperfusion (I/R)-related adverse effects. Using a porcine model of clinical cardiac surgery on CPB, we tested the effects of supplementary AT on myocardial and lung I/R injury. METHODS: Twenty pigs undergoing 60-min aortic clamping and 75-min normothermic perfusion were randomized in a blinded setting to receive an intravenous (i.v.) bolus of AT (250 IU/kg) (AT group, n = 10) or placebo (n = 10) 15 min before aortic declamping. An additional group of five animals received 500 IU/kg AT in an open-label setting (AT+). Thrombin-antithrombin complexes (TAT), activated clotting times (ACT), AT and myeloperoxidase (MPO) activities, troponin T, and several hemodynamic parameters were measured before CPB and after weaning from CPB up to 120 min after aortic declamping. After 120 min of reperfusion, myocardial and lung biopsies were taken for histological examination. RESULTS: AT effectively inhibited coagulation as assessed by ACT. In the AT and AT+ groups only, cardiac output (CO) and stroke volume (SV) showed a trend of post-ischemic recovery during the first 15 min after CPB. AT-attenuated reperfusion induced an increase in pulmonary arterial diastolic pressure (PAPD) but did not have significant effects on systemic or pulmonary vascular resistance. The effects of AT on SV, CO, and PAPD were fortified in the AT+ group. AT did not show effects on inflammatory changes in either myocardial or pulmonary tissue specimens. AT did not reduce post-ischemic troponin T release. CONCLUSION: Supplementary AT, in doses with significant anticoagulant effect, did not alleviate myocardial I/R injury in terms of histological inflammatory changes or post-ischemic troponin T release. Instead, however, AT-attenuated reperfusion induced an increase in pulmonary pressure after CPB. Mechanisms and clinical implications of these effects remain to be explored.

Lack of renoprotective effect of i.v. N-acetylcysteine in patients with chronic renal failure undergoing cardiac surgery.

BACKGROUND: Pre-existing chronic renal failure is a significant risk factor for acute renal failure (ARF) after cardiac surgery. N-acetylcysteine (NAC) has been shown to prevent contrast media-induced ARF. Our objective was to evaluate whether i.v. NAC has renoprotective effects in patients with mild renal failure undergoing cardiac surgery. METHODS: In this prospective, randomized, double-blind study, 80 patients with mild to moderate renal failure undergoing elective heart surgery with cardiopulmonary bypass were recruited. All received either i.v. NAC (n=38) or placebo (n=39) at induction of anaesthesia and then up to 20 h. Urine N-acetyl-beta-D-glucosaminidase (NAG) and urine creatinine ratio, plasma creatinine, and serum cystatin C levels indicated renal function. RESULTS: Levels of urinary NAG/creatinine ratio, plasma creatinine and serum cystatin C did not significantly differ between NAC and placebo groups during five postoperative days. Urine NAG/creatinine ratio increased over 30% in 100% of patients in the NAC group vs 92.3% in the placebo group (P=0.081). Plasma creatinine increased by 25% from baseline or over 44 mumol litre(-1) in 42.1% in NAC group vs 48.7% in placebo group (P=0.560). Serum cystatin C exceeded 1.4 mg litre(-1) in 78.9% in NAC group vs 61.5% in placebo group (P=0.096). CONCLUSIONS: Prophylactic treatment with i.v. N-acetylcysteine had no renoprotective effect in patients with pre-existing renal failure undergoing cardiac surgery.

Thrombin generation during reperfusion after coronary artery bypass surgery associates with postoperative myocardial damage.

BACKGROUND: Cardiopulmonary bypass and coronary artery bypass grafting (CABG) result in significant thrombin generation and activation of fibrinolysis. Thrombin contributes to myocardial ischemia-reperfusion injury in animal studies, but the role of thrombin in myocardial damage after CABG is unknown. OBJECTIVES: We measured thrombin generation and fibrin turnover during reperfusion after CABG to evaluate their associations with postoperative hemodynamic changes and myocardial damage. METHODS: One hundred patients undergoing primary, elective, on-pump CABG were prospectively enrolled. Plasma prothrombin fragment F(1+2) and D-dimer were measured preoperatively and at seven time points thereafter. Mass of the Mb fraction of creatine kinase (Ck-Mbm) and troponin T (TnT) were measured on the first postoperative day. RESULTS: Reperfusion induced an escalation of thrombin generation and fibrin turnover despite full heparinization. F(1+2) during early reperfusion associated with postoperative pulmonary vascular resistance index. F(1+2) at 6 h after protamine administration correlated with Ck-Mbm (r = 0.40, P < 0.001) and TnT (r = 0.44, P < 0.001) at 18 h postoperatively. Patients with evidence of myocardial damage (highest quintiles of plasma Ck-Mbm and TnT) had significantly higher F(1+2) during reperfusion than others (P < 0.002). Logistic regression models identified F(1+2) during reperfusion to independently associate with postoperative myocardial damage (odds ratios 2.5-4.4, 95% confidence intervals 1.04-15.7). CONCLUSIONS: Reperfusion caused a burst in thrombin generation and fibrin turnover despite generous heparinization. Thrombin generation during reperfusion after CABG associated with pulmonary vascular resistance and postoperative myocardial damage.

Fatal anaphylactic reaction to protamine after femoropopliteal by-pass surgery.

BACKGROUND AND AIMS: Administration of protamine might cause serious complications especially in patients treated preoperatively with NPH insulin. MATERIAL AND METHODS: A case report. RESULTS AND CONCLUSION: Administration of protamine sulphate caused fatal anaphylactic reaction to a diabetic patient undergoing femoropopliteal by-pass surgery. Care should be taken when administering protamine to a patient treated preoperatively with NPH insulin and the possibility of an anaphylactid reaction to protamine have to be kept in mind.

The effect of dopexamine on regional tissue oxygenation, systemic inflammation and amino acid exchange in major abdominal surgery.

BACKGROUND: Beta-adrenergic agents are frequently used to improve cardiac performance in surgical and intensive care patients. Beta-adrenergic agents have metabolic and anti-inflammatory effects in addition to their cardiovascular effects. Splanchnic metabolic activity increases in response to surgery and inflammation. Dopexamine is believed to favor blood flow distribution to the splanchnic region. METHODS: We investigated the effect of dopexamine, started before major abdominal surgery, on postoperative patterns of systemic and regional blood flow, metabolic response, and markers of inflammation. Twenty-one patients undergoing major abdominal surgery were studied. All patients were stabilized preoperatively to predefined hemodynamic endpoints with fluids. After preoperative measurement of systemic and splanchnic oxygen transport and splanchnic lactate, glutamine and alanine exchange and blood levels of tumor necrosis factor (TNF) and interleukin-6 (IL-6), the patients were randomized to receive an infusion of dopexamine at 0.5 microg kg(-1) min(-1) (group 1) or 2.0 microg kg(-1) min(-1) (group 2) or placebo. Measurements were repeated at 6 h and 24 h after the end of the operation and the blood levels of cytokines also at 36 h postoperatively. RESULTS: Dopexamine evoked an increase in cardiac index preoperatively. Postoperatively, there was no difference between the groups in systemic and regional hemodynamics or oxygen transport: cardiac index, splanchnic blood flow and oxygen delivery increased similarly in each group. Accordingly, systemic oxygen extraction decreased. Glutamine, alanine and lactate exchange did not differ between the groups. The only metabolic change was an increased splanchnic uptake of alanine, which also was unaffected by dopexamine. There was no difference between the groups in TNF and IL-6 levels; TNF level did not change, while IL-6 level increased in response to surgery. CONCLUSIONS: Dopexamine, when added to a preoperative stabilization protocol with fluids, did not augment the postoperative hemodynamic response, and had no effect on postoperative metabolic and inflammatory responses.

Accelerated splanchnic amino acid uptake after cardiac surgery.

Energy expenditure increases after cardiac surgery, but changes in peripheral tissue metabolism do not explain this increase. We hypothesized that the splanchnic region is a major contributor to the postoperative hypermetabolism, and this should be reflected in the exchange of amino acids across the splanchnic bed. We measured systemic and regional (splanchnic and leg) amino acid exchange, oxygen uptake and hemodynamics in 22 elective coronary bypass grafting patients postoperatively after arrival to the intensive care unit, 2 h later, and after stabilization of hemodynamics. Splanchnic uptake of glutamine (50 +/- 37 micromol/min/m2 to 78 +/- 37 micromol/min/m2, P < 0.05) and three of the gluconeogenetic amino acids, alanine (115 +/- 52 micromol/min/m2 to 183 +/- 70 micromol/min/m2, P < 0.05), serine (18 +/- 10 micromol/min/m2 to 26 +/- 13 micromol/min/m2) and threonine (20 +/- 8 micromol/min/m2 to 28 +/- 8 micromol/min/m2) increased during the observation period. Similarly, the oxygen consumption by the splanchnic region increased while splanchnic blood flow remained stable. A correlation between oxygen and amino acid uptake by the splanchnic bed was observed during the study period. Femoral exchange of glutamine and alanine did not change, although femoral blood flow and oxygen consumption increased during rewarming. High metabolic activity was observed in the splanchnic region during the early postoperative phase after hypothermic cardiac surgery. The increased plasma amino acid concentration indicates a release of amino acids from other sources than the peripheral muscle.

Preoperative glutamine loading does not prevent endotoxemia in cardiac surgery.

BACKGROUND: The presence of endotoxemia is relatively common in cardiac surgery patients and it may modify the metabolic and hemodynamic responses peri- and postoperatively. Impaired gut fuel metabolism may contribute to the disturbed function and deterioration of the intestinal mucosal barrier and the development of bacterial translocation and endotoxemia. Glutamine may protect the gut mucosal barrier during marginal or insufficient perfusion. METHODS: We studied the effects of glutamine supplementation on endotoxemia and blood levels of tumor necrosis factor (TNF) during and after extracorporeal circulation (ECC) and the effects of endotoxemia on systemic and regional (splanchnic and leg) hemodynamics and metabolism after cardiac surgery. Nineteen elective coronary bypass patients were randomly assigned to receive preoperatively for 12 h either an infusion of glucose and a balanced amino acid solution (AA-group) or a solution containing 1/5 of total nitrogen as alanyl-glutamine (ALAGLN-group). RESULTS: Glutamine and amino acid loading before ECC did not protect from peri- or postoperative endotoxemia. Endotoxemia was detected in 5 vs. 7 of patients during ECC and 6 vs. 5 of patients postoperatively in the ALAGLN-group vs. AA-group, respectively. More than half of the patients at every measurement had an increased level of TNF. There was no consistent difference between the arterial and hepatic vein endotoxin- or TNF-concentrations. Endotoxemia did not modify systemic or regional hemodynamics and metabolism after cardiac operation. CONCLUSION: Glutamine did not prevent endotoxemia during or after cardiac surgery. An increased level of TNF was common and observed also in some patients without endotoxemia. Endotoxemia did not modify regional or whole-body metabolic patterns or hemodynamics.

Hypermetabolism and increased peripheral release of amino acids after subarachnoidal hemorrhage and its operative treatment.

The metabolic response to surgery for acute subarachnoidal hemorrhage and its modification by amino acid infusions was studied. Thirty patients with acute subarachnoidal hemorrhage were randomly assigned to receive for 12 h either an infusion of glucose and a balanced amino acid solution (1.68 MJ = 400 kcal/d and 0.15 gN.kg-1.d-1; group AA) or a glucose and a solution containing 20% of total nitrogen as alanyl-glutamine (1.68 MJ = 400 kcal/d and 0.15 gN.kg-1.d-1; group ALAGLN). A separate control group received glucose alone (1.68 MJ = 400 kcal/d). The infusions started 12 h after operation. All patients received corticosteroids. Despite a higher arterial glutamine concentration in the ALAGLN-group (791 +/- 195 mumol/L vs. AA 581 +/- 112 mumol/L, and control 571 +/- 82 mumol/L; p < 0.05) the net release of glutamine from the leg was similar in all groups (ALAGLN: 39 +/- 47 mumol/min, AA: 26 +/- 18 mumol/min, and control: 24 +/- 14 mumol/min, NS). Also the release of alanine (ALAGLN: 35 +/- 24 mumol/min, AA: 34 +/- 24 mumol/min, and control: 30 +/- 18 mumol/min) and total amino acids (ALAGLN: 133 +/- 131 mumol/min, AA: 125 +/- 98 mumol/min, and control: 112 +/- 72 mumol/min) were similar in all groups. All groups were characterized by a pattern of preoperative hypermetabolism that persisted after the operation. The hypermetabolism was not related to increased peripheral oxygen consumption, since femoral oxygen consumption (VO2) represented only 3% of the whole body VO2-.

Effect of single-dose omeprazole and ranitidine on gastric juice acidity and volume in patients undergoing laparotomy.

The effects of oral omeprazole and oral ranitidine on gastric fluid volume and pH were compared in 95 elective surgical patients, randomly assigned to one of three groups. The patients received either 80 mg of omeprazole or 300 mg of ranitidine orally at 6.00 on the morning of surgery. One third of the patients received no antacid therapy. Following induction, a no. 18 nasogastric tube was passed into the stomach and all available gastric fluid was aspirated. pH and volumes were measured. In the omeprazole- and ranitidine-treated groups, the mean pH was > 5.4 after induction, at completion of surgery and 1 h after operation, although at least one patient in both groups had pH < 2.5. The volumes of gastric aspirates were reduced equally by both drugs. Two patients in the omeprazole group, none in the ranitidine group and eight in the control group (26%) had pH < 2.5 with volume > 25 ml at induction. Both drugs appeared to be effective in reducing the volume of intragastric fluid and acidity to acceptable values.

The effect of prophylactic use of famotidine, ranitidine, and sodium citrate in upper abdominal surgery.

The effects of famotidine (40 mg), ranitidine (300 mg) and sodium citrate (30 ml) on the gastric pH and volume were tested in 114 patients undergoing upper abdominal surgery. Gastric content was aspirated through a multiorifice tube immediately after intubation, at the end of operation and after a recovery room period of one hour. All three drug regimens significantly increased the mean gastric pH value compared with the control group. Famotidine and ranitidine reduced the volume of gastric content in comparison with sodium citrate and the control group. However, the difference was significant only in the recovery room sample.