Is Toupet fundoplication the procedure of choice for treating gastroesophageal reflux disease? Results of a prospective randomized experimental trial comparing three major antireflux operations in a porcine model.

BACKGROUND: Gastroesophageal reflux disease (GERD) is among the most common dysfunctions of the upper gastrointestinal tract. It interferes with quality of life and is a risk factor for the development of adenocarcinoma in the lower esophagus. Laparoscopic fundoplication is an effective treatment of GERD, but the physiologic mechanisms of the different available procedures had not been investigated to date. METHODS: In this study, 28 German Landrace pigs underwent baseline manometry and 24-h pH monitoring followed by myotomy to induce reflux esophagitis. After new-onset reflux was proved, the pigs were randomized to groups based on four treatments: total fundoplication, anterior hemifundoplication, posterior hemifundoplication, and control. On days 10 and 60 after the intervention, the effectiveness of the different fundoplication modifications was compared with that of the control subjects by 24-h pH monitoring manometry. Finally, the pigs were killed, after which the minimum volume and pressure required to breach the gastroesophageal junction were recorded. RESULTS: After myotomy, a significant increase in the reflux could be confirmed. The findings after fundoplication showed a significant decrease in the fraction of time that the pH fell below four and an increase in the vector volume compared with the measurement after myotomy. Total fundoplication and posterior hemifundoplication were highly effective, whereas measurements after anterior fundoplication still showed increased fraction times. Pharmacologic stimulation with pentagastrin showed an increase in the vector volume of the esophageal sphincter. CONCLUSIONS: Total fundoplication and posterior hemifundoplication are potent operations for the treatment of GERD. Anterior hemifundoplication reduces the reflux as well, but the effects are significantly less than with total and posterior fundoplication. Pharmacologic stimulation showed excellent results after posterior hemifundoplication, and a tendency to overcorrection was shown after total fundoplication.

Administration of bovine polymerized haemoglobin before and during coronary occlusion reduces infarct size in rabbits.

BACKGROUND: Haemoglobin-based oxygen carriers (HBOC) seem to increase the risk of mortality and myocardial infarction in clinical trials. Therefore, we designed this randomized placebo-controlled animal study to evaluate the effects of prophylactic and therapeutic administration of HBOC in a myocardial ischaemia-reperfusion model with respect to infarct size and areas of impaired perfusion (no reflow, NR). METHODS: Thirty-two anaesthetized, mechanically ventilated rabbits were randomized to one of the four groups. Group G1 received 0.4 g kg(-1) i.v. HBOC-200 25 min before coronary artery occlusion, G2 received the same dose i.v. 10 min after occlusion, and G3 and 4 received i.v. saline. G1, 2, and 3 were subjected to 30 min occlusion of left coronary artery followed by 240 min of reperfusion. G4 was treated without ischaemia-reperfusion. Measurement included assessment of the area at risk and infarct size using triphenyltetrazolium chloride stain and areas of NR using thioflavin stain. Ischaemia-reperfusion was confirmed by microspheres technique. RESULTS: Infarct size as a percentage of the area at risk was significantly reduced in G1 [25 (sd 13)%, P=0.026] and G2 [22 (20)%, P=0.009] compared with G3 [48 (17)%]. The areas of NR in percentage of the area at risk [G1, 26 (15)%; G2, 34 (22)%; G3, 36 (12)%; G4, 5 (3)%] did not differ between the groups of animals undergoing coronary occlusion and reperfusion. CONCLUSIONS: Prophylactic and therapeutic administration of HBOC-200 reduces infarct size in myocardial ischaemia and reperfusion in rabbits. This reduction of infarct size is not accompanied by an improvement of areas of NR.

Effects of a prophylactic or therapeutic application of perflubron emulsion on myocardial ischaemia-reperfusion injury in rats.

BACKGROUND AND OBJECTIVE: The efficacy of administering a perfluorochemical-based oxygen therapeutic such as perflubron emulsion (Oxygen) prior to ischaemia is currently unknown, although there is evidence for potential beneficial effects for the perioperative treatment in cardiac risk patients. This experimental study investigated the efficacy of perflubron emulsion in preventing reperfusion injury and myocardial infarction size after coronary ischaemia and reperfusion. The perflubron emulsion was given either in a prophylactic manner, prior to induction of myocardial ischaemia, or as a therapeutic agent given during ischaemia. METHODS: Thirty-two anaesthetized and mechanically ventilated rats were subjected to 25 min occlusion of the left coronary artery followed by 120 min reperfusion. Animals were randomized to one of four groups:Group 1 was treated with administration of 6 g kg (-1) intravenous perflubron emulsion 25 min before occlusion; Group 2 received the same dose 10 min after occlusion; and Groups 3 and 4 received no perflubron emulsion. Inspired O2 (FiO2) concentration was maintained at 1.0 in Groups 1, 2 and 3 and at 0.35 in Group 4. RESULTS: Neither prophylactic nor therapeutic perflubron emulsion treatment reduced infarct size measurements by triphenyltetrazolium-chloride staining or severity of cardiac arrhythmias in comparison to the hyperoxic control group. However, prophylactic application of perflubron emulsion reduced areas of impaired perfusion vs. Group 3 assessed by in vivo staining with Thioflavin-S while no significant effect was seen in Groups 2 and 4 vs. 3. Density of DNA single-strand breaks in the ventricle was increased in all groups ventilated with 100% oxygen. CONCLUSION: Although administration of perflubron emulsion did not reduce infarct size, areas of impaired perfusion were significantly mitigated when perflubron emulsion was administered prior to coronary occlusion. However, a high oxygen concentration may provoke DNA strand breaks during reperfusion after ischaemia. Further studies must clarify whether enhanced oxidative stress outweighs the advantage of improved areas of impaired perfusion following perflubron emulsion.

[Swollen and elongated uvula after general anaesthesia]. / Uvula-Schwellung und -Elongation nach Intubationsnarkose.

Localized pathological changes of the uvular are rare but potentially life-threatening complications after general anaesthesia with endotracheal intubation. A case of postoperative swollen and elongated uvula after general anaesthesia in a prone position is presented. A mechanical trauma seems to be the most likely etiology.

Intraoperative anisocoria in a child during renal transplantation.

Anisocoria during anaesthesia may indicate a serious neurological condition. Assessment by physical examination and diagnostic imaging is limited during surgery and anaesthesia. We report a case of a boy undergoing renal transplantation, who suffered from anisocoria during general anaesthesia. A transcranial sonography was performed, showing no intracranial pathology. However, retinal hypoperfusion detected with orbital doppler sonography was a plausible explanation for anisocoria.

Pre-incisional epidural ropivacaine, sufentanil, clonidine, and (S)+-ketamine does not provide pre-emptive analgesia in patients undergoing major pancreatic surgery.

BACKGROUND: The concept of pre-emptive analgesia remains controversial. This prospective, randomized, and double-blind study compared epidural administration of ropivacaine 2 mg ml(-1), sufentanil 0.5 microg ml(-1), clonidine 3 microg ml(-1), and S(+)-ketamine 0.25 mg ml(-1) (study solution) given before incision with the same combination started at the end of the operation. METHODS: After testing the stability of the solution using high performance liquid chromatography (HPLC) and examining 12 patients for possible side-effects in comparison with the epidural infusion of ropivacaine 2 mg ml(-1) and sufentanil 0.5 microg ml(-1), 30 patients undergoing major pancreatic surgery were recruited into the study. Before induction of anaesthesia, an epidural catheter was inserted (TH6-8). Patients in Group 1 received a bolus of 8 ml followed by a continuous infusion (8 ml h(-1)) of the study solution before induction of anaesthesia. In Group 2, patients received the same volume of saline before operation, the study solution was started at the end of surgery. After operation, the infusion was maintained for at least 96 h using a patient-controlled epidural analgesia (PCEA) pump in both groups. Patients were evaluated up to the seventh postoperative day for pain and side-effects. RESULTS: Visual analogue scale (VAS) values at rest were as follows: G1 vs G2: 24 h, 19 (sd 23) vs 6 (13); 48 h, 4 (10) vs 11 (21); and 72 h, 12 (22) vs 13 (21). VAS values during coughing and mobilization were also comparable. Total volume of epidural infusion was 904 (114) ml in G1 vs 892 (154) ml in G2. The incidence of side-effects (nausea, vomiting, and motor block) was low and not different between the groups. CONCLUSIONS: Pre-incisional epidural analgesic infusion did not provide pre-emptive analgesia compared with administration started at the end of surgery, but both groups had low pain scores.

[An undiagnosed plasma cell myeloma. Complication after performing spinal anesthesia]. / Ein nichtdiagnostiziertes Plasmozytom. Spinalanästhesie mit Folgen.

A male patient developed neurological deficits after an uneventful spinal anesthesia. After 2 months without any improvement an epidural hematoma was presumed. Magnet resonance imaging detected inflammatory tissue and destruction at lumbar levels L2/3. The inflammatory tissue had to be removed via laminectomy. Histology of the excised tissue revealed a plasma cell myeloma that was not diagnosed prior to spinal anesthesia 2 months previously.

[Continuous interscalenic nerve block in a 3 year old child after amputation of upper extremity]. / Kontinuierliche interscalenäre Plexusblockade bei einem dreijährigen Kind nach Armamputation -- Ein Fallbericht.

Amputations of extremities, especially in the childhood, impose high demands on the perioperative management. Apart from the intraoperative care of these children, the postoperative pain therapy has to do one's utmost in the avoidance of the development of phantom limb pain, which can, especially in the childhood, be associated with far reaching psychological consequences. We report the case of a 3-year old boy who had to undergo exarticualtion of his left arm due to an osteosarcoma of the humerus. The perioperative pain management was performed by a preoperatively placed interscalene catheter and infusion of 0.2 % ropivacaine. Within the first six days postoperatively complete pain relief could be ensured with this analgetic regimen.

Effects of prophylactic or therapeutic application of bovine haemoglobin HBOC-200 on ischaemia-reperfusion injury following acute coronary ligature in rats.

BACKGROUND: Haemoglobin-based oxygen carriers (HBOCs) are assessed as blood substitutes in patients with perioperative anaemia including patients at risk for perioperative cardiac ischaemia. There is controversy as to whether HBOCs are beneficial or deleterious during ischaemia-reperfusion (I-R). Therefore the effects of HBOC-200 on I-R injury were evaluated in a randomized placebo-controlled animal trial. METHODS: Animals were randomized to receive either placebo i.v. without I-R (sham group, n=9), placebo i.v. with I-R (control group, n=10), HBOC-200 0.4 g kg(-1) i.v. prior to I-R (prophylaxis group, n=12) or HBOC-200 0.4 g kg(-1) i.v. during I-R (therapy group, n=15). I-R consisted of 25 min of acute ligature of the left coronary artery followed by 120 min of reperfusion. Measurements included assessment of the area at risk and infarct size using triphenyl tetrazolium chloride (TTC) stain, DNA single-strand breaks (in situ nick translation with autoradiography/densitometry) and cardiac arrhythmias. RESULTS: Infarct size within the area at risk was 62 (sd 15)% (control), 46 (10)% (prophylaxis, P<0.025 vs control) and 61 (9)% (therapy, P<0.85 vs control). The frequency of DNA single-strand breaks was reduced vs control in the sham (P<0.01) and prophylaxis (P<0.04) groups and was almost the same in the therapy group (P<0.75). The severity of cardiac arrhythmias during ischaemia was lower compared with control in the sham (P<0.001) and prophylaxis (P<0.039) groups, but there was no difference in the therapy group. CONCLUSION: This study demonstrates that neither prophylactic nor therapeutic application of the cell-free haemoglobin solution HBOC-200 aggravates cardiac I-R injury. Furthermore, the prophylactic approach may offer a new opportunity for pretreatment of patients at risk for perioperative ischaemic cardiac events.

Effects of isovolaemic haemodilution on oxygenation of liver and skeletal muscle.

BACKGROUND AND OBJECTIVE: Hydroxyethyl starch is frequently used for volume substitution during surgical procedures and for isovolaemic haemodilution. Haemodilution has also been shown to improve tissue oxygen tension in skeletal muscle: However, effects of this volume substitute on tissue oxygen tension of the liver during haemodilution remains unknown. METHODS: Fourteen foxhounds were anaesthetized with fentanyl/midazolam and mechanically ventilated with 30% oxygen. Following splenectomy animals were randomly assigned to a control group without haemodilution but fluid substitution with Ringer's lactate (Group C) or underwent isovolaemic haemodilution to a haematocrit of 25% with hydroxyethyl starch 70/0.5 (Group H). Haemodynamic parameters and oxygen transport during 100 min following isovolaemic haemodilution were measured. Liver oxygen tension was recorded using a flexible polarographic electrode tonometer, whereas in the muscle a polarographic needle probe was used. RESULTS: Animal characteristics and baseline haematocrit were similar in both groups. At baseline the tissue oxygen tension of liver and skeletal muscle were not different between groups. Haemodilution with hydroxyethyl starch 70/0.5 provided augmentation of mean liver tissue oxygen tension (baseline: 46 +/- 13 mmHg; 20 min: 60.3 +/- 12 mmHg; 60 min: 60 +/- 16 mmHg; 100 min: 63 +/- 16 mmHg; P < 0.05 vs. baseline), while oxygen tensions in Group C remained unchanged (baseline: 48 +/- 16 mmHg; 20 min: 52 +/- 19 mmHg; 60 min: 49 +/- 12 mmHg; 100 min: 52 +/- 16 mmHg) and no differences could be detected between groups. Oxygen tension in skeletal muscle changed as follows: Group H - baseline: 24 +/- 32 mmHg; 20 min: 32 +/- 3 mmHg; 60 min: 33 +/- 7 mmHg; 100 min: 33 +/- 11 mmHg. Group C - baseline: 22 +/- 6 mmHg; 20 min: 21 +/- 3 mmHg; 60 min: 24 +/- 4 mmHg; 100 min: 18 +/- 4 mmHg (P < 0.05 vs. baseline, p < 0.05 vs. Group C). CONCLUSION: In this animal model, isovolaemic haemodilution with hydroxyethyl starch 70/0.5 increased tissue oxygen tension in liver and skeletal muscle in comparison with baseline values. However, when compared between groups haemodilution only resulted in an increase of tissue oxygen tension in the muscle but not in the liver.

Ambulatory long-term pH monitoring in pigs.

BACKGROUND: pH monitoring has been established as the "gold standard" in the diagnosis of gastroesophageal reflux. Evaluation of experimental antireflux therapy should therefore also include this technique, but a suitable technique in an experimental model did not exist so far. The aim of our study was to establish a reliable method for the evaluation of an experimental reflux model in pigs. METHODS: A total of 33 German Landrace pigs with an average body weight of 56 (50.2-67.2) kg were included. pH monitoring was performed before and after open cardiomyotomy in each animal. All manipulations were performed under general anesthesia. After manometric localization of the gastroesophageal high-pressure zone, a standard pH probe was inserted into the pharynx through a small needle-punctured canal on the side of the animal's snout and placed under endoscopic guidance with the proximal sensor 3 cm above the lower esophageal sphincter (LES) and the distal sensor in the stomach for reference. The harness to carry the pH recorder on the animal's back consisted of a modified belly strap that enabled the animal to move around without limitation. For analysis the same threshold levels were defined as in humans. Gastroesophageal reflux was induced by cardiomyotomy. RESULTS: The placement of the standard pH probe was possible in all cases. Inserting the probe on the side of the snout left the animals free to nuzzle, which complies with the normal habits of pigs, without breaking the probes and without being compromised in their natural behavior. Repeated punctures for multiple measurements were easily feasible. We performed up to three examinations in each individual animal. Recording was performed for 48 h. A mean number of 67.3 (+/-9.7) acidic refluxes were registered. The mean number of long acidic refluxes was 3.2 (+/-0.75). For an average total time of 75.5 (+/-14.3) min the pH was below 4 accounting for a fraction time pH below 4 of 3.5% (+/-0.68%). Following cardiomyotomy the number of acidic refluxes increased significantly to 166.1 (+/-21.8) and the number of long refluxes to 17.74 (+/-3.35). The total time of pH below 4 increased to 371.3 (+/-62) min so that the fraction time pH below 4 was 14.5% ( p = 0.0006). CONCLUSION: pH monitoring should be mandatory in any investigation of antireflux therapy. Our method is easy and secure to perform. It is suitable for other gastrointestinal investigations (Bilitec, long-term manometry) that could be carried out using the same technique. The described data represent the basis for other investigations of experimental antireflux therapy.