Intranasal cooling with or without intravenous cold fluids during and after cardiac arrest in pigs.

BACKGROUND: Intranasal balloon catheters circulated with cold saline have previously been used for the induction and maintenance of selective brain cooling in pigs with normal circulation. In the present study, we investigated the feasibility of therapeutic hypothermia initiation, maintenance and rewarming using such intranasal balloon catheters with or without addition of intravenous ice-cold fluids during and after cardiac arrest treatment in pigs. MATERIAL AND METHODS: Cardiac arrest was induced in 20 anaesthetised pigs. Following 8 min of cardiac arrest and 1 min of cardiopulmonary resuscitation (CPR), cooling was initiated after randomisation with either intranasal cooling (N) or combined with intravenous ice-cold fluids (N+S). Hypothermia was maintained for 180 min, followed by 180 min of rewarming. Brain and oesophageal temperatures, haemodynamic variables and intracranial pressure (ICP) were recorded. RESULTS: Brain temperatures reductions after cooling did not differ (3.8 +/- 0.7 degrees C in the N group and 4.3 +/- 1.5 degrees C in the N+S group; P=0.47). The corresponding body temperature reductions were 3.6 +/- 1.2 degrees C and 4.6 +/- 1.5 degrees C (P=0.1). The resuscitation outcome was similar in both groups. Mixed venous oxygen saturation was lower in the N group after cooling and rewarming (P=0.024 and 0.002, respectively) as compared with the N+S group. ICP was higher after rewarming in the N group (25.2 +/- 2.9 mmHg; P=0.01) than in the N+S group (15.7 +/- 3.3 mmHg). CONCLUSIONS: Intranasal balloon catheters can be used for therapeutic hypothermia initiation, maintenance and rewarming during CPR and after successful resuscitation in pigs.

Intranasal selective brain cooling in pigs.

BACKGROUND: Special clinical situations where general hypothermia cannot be recommended but can be a useful treatment demand a new approach, selective brain cooling. The purpose of this study was to selectively cool the brain with cold saline circulating in balloon catheters introduced into the nasal cavity in pigs. MATERIAL AND METHODS: Twelve anaesthetised pigs were subjected to selective cerebral cooling for a period of 6 h. Cerebral temperature was lowered by means of bilaterally introduced nasal balloon catheters perfused with saline cooled by a heat exchanger to 8-10 degrees C. Brain temperature was measured in both cerebral hemispheres. Body temperature was measured in rectum, oesophagus and the right atrium. The pigs were normoventilated and haemodynamic variables were measured continuously. Acid-base and electrolyte status was measured hourly. RESULTS: Cerebral hypothermia was induced rapidly and within the first 20 min of cooling cerebral temperature was lowered from 38.1+/-0.6 degrees C by a mean of 2.8+/-0.6 to 35.3+/-0.6 degrees C. Cooling was maintained for 6 h and the final brain temperature was 34.7+/-0.9 degrees C. Concomitantly, the body temperature, as reflected by oesophageal temperature was decreased from 38.3+/-0.5 to 36.6+/-0.9 degrees C. No circulatory or metabolic disturbances were noted. CONCLUSIONS: Inducing selective brain hypothermia with cold saline via nasal balloon catheters can effectively be accomplished in pigs, with no major disturbances in systemic circulation or physiological variables. The temperature gradients between brain and body can be maintained for at least 6 h.

Peribiliary plexa--important pathways for shunting of iodized oil and silicon rubber solution from the hepatic artery to the portal vein. An experimental study in rats.

OBJECTIVES: Iodized oil is commonly used in chemoembolization of hepatic tumors, and silicon rubber solution is used for casting studies of hepatic tumor vasculature. Understanding the distribution patterns of iodized oil and silicon rubber solution is of significance in the refinement of iodized oil techniques and proper interpretation of hepatic tumor vascular studies. In this study, the location for iodized oil and silicon rubber solution shunting from the hepatic artery to the portal vein was identified. METHODS: Iodized oil and silicone rubber solution were injected into the hepatic artery in rats. The porta hepatis and the liver periphery were examined using in vivo microscopy. RESULTS: Iodized oil and silicone rubber solution had identical distribution patterns in the hepatic circulation. Both were shunted in large quantities from the hepatic artery into the portal vein through the peribiliary plexa. Other potential shunting sites did not contribute to the shunting. CONCLUSIONS: Though of different chemical natures, iodized oil and silicon rubber solution share similar distribution patterns in the liver. Hepatic arterioportal shunting of these substances occurs via the peribiliary plexa.

Experimental hepatic artery embolization with Gelfoam powder. Microfil perfusion study of the rabbit liver.

After hepatic artery embolization with Gelfoam powder in five rabbits, two colors of Microfil (silicone rubber solution) were perfused into the aorta and the portal vein to study hepatic microcirculation under a dissection microscope. In three of the animals, many intrahepatic arterial branches and portions of the hepatic sinusoids were perfused with the arterial Microfil (orange color), whereas in the other two animals no orange Microfil was found in the liver. In the three animals, occlusions of the hepatic artery were random in distribution and often segmental, and arteries as small as 50 microns in diameter were involved. In the latter group, levels of arterial occlusion could not be evaluated. Microcollaterals developed through the capsular artery, peribiliary arterial plexus, and vasa vasora of the portal vein.

Embolization of the spleen for treatment of splenomegaly and hypersplenism in patients with portal hypertension.

Splenectomy in cases of hypersplenism involves significant risk of serious complications, including infection, hemorrhage, portal systemic thrombosis, and necrosis of the stomach or small bowel. Alternative procedures such as transcatheter embolization have been associated with a high frequency of splenic or subphrenic abscess, preventing clinical use. We used partial splenic embolization under careful antibiotic protection to successfully treat thrombocytopenia in 18 patients, most of whom had hypersplenism and splenomegaly secondary to portal hypertension. Of the 30 embolizations performed, the only serious complications encountered were abscess in two patients (who had almost total infarction) and four cases of splenic vein thrombosis. We investigated the possible effect of splenic embolization on portal venous pressure in three patients and found no pressure change.

Microvasculature architecture of small liver metastases in man. A correlation between microfil vascular preparations and histologic sections.

The hepatic artery and the portal vein of 12 human cadaver livers with metastases of various sizes and origins were injected with Microfil. The microvascular appearances of the metastases were studied in order to receive an explanation to findings at angiography and contrast enhanced computed tomography. Histologic examinations were also performed of Microfil-injected specimens.

Postmortem examination of the blood supply and vascular pattern of small liver metastases in man.

Thirteen human cadavers with liver metastases were examined. Microfil was injected into the portal vein and hepatic artery. The liver metastases were examined under dissecting microscope, and their vascular supply and patterns were registered. It was found that most metastases had both arterial and portal supply even if the arterial supply dominated. Extensive filling of tumor vessels was observed in both lobes in one liver in which the portal vein of one lobe and the hepatic artery of the other was injected (i.e., the same kind of metastases could be filled from either the hepatic artery or the portal vein). It is suggested that the findings could be of great importance in planning treatment of patients with liver metastases.

Interventional radiology of the biliary tract. Metallic stents.

Biliary metallic stents were placed in 18 patients with bile duct obstruction. Six patients received Gianturco stents and 14 Wall-stents. Results of these tests are discussed.

Localization of carcinoids and pheochromocytomas with vein catheterization and amine determination.

Selective catheterization of hepatic, intestinal and adrenal veins with blood sampling for serotonin and catecholamine determination was evaluated regarding its use in the diagnosis, location and characterization of carcinoids and pheochromocytomas. Catheterization of intestinal veins via the transhepatic route and of the adrenal veins via the femoral and caval veins was performed in 49 patients without major complications. High pressure liquid chromatography with electrochemical detection was used to quantitate norepinephrine and epinephrine in plasma and serotonin in plasma and whole blood. Serotonin in plasma was also determined by an enzymatic procedure. In 30 patients with suspected or verified carcinoid tumors concentration of serotonin in tumor-draining veins was clearly elevated in all patients but one. In this patient, who previously had been treated with temporary liver dearterialization, the serotonin concentration in the hepatic vein was within the normal range in spite of the existence of liver metastases. Hyperserotoninemia was registered in one patient without detectable carcinoid tumor cells. In three patients determination of norepinephrine and epinephrine in adrenal venous blood diagnosed a hyperplasia and tumors in the adrenal medulla. In these cases angiography and computed tomography were negative. Microscopic analyses revealed serotonin in all carcinoids and substance P-like immunoreactivity in a large percentage of these tumors. PP-like and glucagon-like immunoreactivity were observed in two endocrine pancreatic tumors. In normal adrenal medulla and in adrenal medullary tumor tissue catecholamine fluorescence and enkephalin-like immunoreactivity were demonstrated. In the two pheochromocytomas ACTH-like, somatostatin-like and calcitonin-like immunoreactivities were identified. The technique with determinations of plasma serotonin and catecholamines in combination with selective catheterization is a useful investigation for the diagnosis, location and follow-up of patients with carcinoids and pheochromocytomas.

Islet cell hyperplasia localized by pancreatic vein catheterization and insulin radioimmunoassay.

A patient with organic hypoglycemia but with normal pancreatic arteriography was investigated with pancreatic vein catheterization for insulin immunoassay. Very high insulin concentrations (1, 130 micronU/ml) were found in a vein draining part of the pancreatic tail. Even though no tumor was found at operation, distal hemipancreatectomy was performed according to the assay findings. Histology and immunohistochemistry revealed a localized islet hyperplasia.

Treatment of liver cancer with regional intraarterial 5-FU infusion.

The results of a retrospective three year study of forty-six patients with cancer of the liver treated with regional intraarterial infusion of 5-FU are reported. No primary mortality was noted. Oblective overall remission rate was 43 per cent. Overall median survival from onset of treatment was six months. The one year survival rate was 33 per cent and the two year survival rate 11 per cent. Patients with an objective response had a significantly prolonged survival as compared with nonresponders, especially in the colorectal group: sixteen months versus four months. Survival was not related to tumor size and involvement of the liver. During treatment 42 per cent of the patients developed extrahepatic metastases. Quality of life was improved in 63 per cent of the patients. The results indicate that infusion therapy induces reasonable response and palliation but is inadequate for the control of extrahepatic tumor growth.

[Percutaneous transhepatic intubation of bile ducts for combined internal and external drainage in extrahepatic cholestasis (author's transl)]. / Perkutane transhepatische Intubation der Gallengänge zur kombinierten inneren und äusseren Drainage bei extrahepatischer Cholestase.

In 37 patients with extrahepatic cholestasis of different origin, percutaneous transhepatic intubation of the bile ducts was performed for combined internal and external drainage. In 5 cases with stones in the extrahepatic bile ducts and in 12 cases with periampullary tumors, the bile ducts were drained preoperatively. In 3 of these patients, temporary drainage was performed because of postoperative complications. Thirteen patients with non-resectable tumors received a permanent drainage as palliation. In 4 patients temporary drainage was performed during radiation/cytostatic therapy. One patient with an iatrogenic bile duct lesion and one patient with an inflammatory tumor in the liver hilum had a drainage catheter placed because a bile duct resection with creation of a biliodigestive anastomosis was not possible. In one patient with a non-resectable periampullary carcinoma the drainage catheter was replaced by a teflon bile duct endoprosthesis inserted by the percutaneous transhepatic approach. The complications of non-operative percutaneous transhepatic bile drainage are discussed.

The YAG laser and Wallstent endoprosthesis for palliation of cancer in the esophagus or gastric cardia.

The need for frequent retreatment is a disadvantage of using endoscopic laser therapy (ELT) alone for palliative treatment of esophageal carcinoma. In this prospective study, therefore, we investigated the potential and feasibility of combining ELT with a self-expanding metallic stent (Wallstent). Twelve patients received ELT followed by stent placement (stent group) and were compared with 39 patients receiving ELT alone (ELT group). Swallowing ability was similar in the two groups. About one-third of the patients who had a short life expectancy, did not appear to benefit from stenting, whereas the interval between retreatments was prolonged by a factor of 2-4 in the remaining patients. Median survivals were 5.5 (range 1.0-23.5) months in patients with stents, and 4.5 (range 1.2-24.6) months in patients without stents. There were few complications related to stenting. In one patient, technical problems caused stent dislodgement into the stomach. Another stent patient died of hemorrhage from an untreated tumor in the stomach, but it was considered unlikely that the bleeding was caused by the stent. In conclusion, this preliminary trial suggests that a Wallstent endoprosthesis, used in combination with laser treatment, may become a valuable tool for prolonging the dysphagia-free interval in selected patients.

[Glucagon-producing endocrine pancreas tumors. Symptoms, diagnosis, localization, therapy and follow-up]. / Glucagonproduzierende endokrine Pankreastumoren. Symptome, Diagnostik, Lokalisation, Therapie und Verlaufskontrolle.

Three cases of glucagonoma syndrome caused by glucagon producing pancreatic islet cell tumors are reported. Modern procedures for diagnosis, localization, and classification are presented and advocated.

[Endoprosthetic dilatation of the vena cava eliminates obstruction in superior vena cava syndrome]. / Endoprotesvidgning av vena cava eliminerar flödeshinder vid vena cava superior-syndrom.

A 62-year-old woman with superior vena cava obstruction (SVCO) secondary to small cell lung cancer was treated with expandable wire stents prior to chemotherapy and irradiation. The treatment resulted in immediate and complete remission of the SVCO symptoms.

Brain temperature in volunteers subjected to intranasal cooling.

PURPOSE: Intranasal cooling can be used to initiate therapeutic hypothermia. However, direct measurement of brain temperature is difficult and the intra-cerebral distribution of temperature changes with cooling is unknown. The purpose of this study was to measure the brain temperature of human volunteers subjected to intranasal cooling using non-invasive magnetic resonance (MR) methods. METHODS: Intranasal balloons catheters circulated with saline at 20°C were applied for 60 min in ten awake volunteers. No sedation was used. Brain temperature changes were measured and mapped using MR spectroscopic imaging (MRSI) and phase-mapping techniques. Heart rate and blood pressure were monitored throughout the experiment. Rectal temperature was measured before and after the cooling. Mini Mental State Examination (MMSE) test and nasal inspection were done before and after the cooling. Questionnaires about the subjects' personal experience were completed after the experiment. RESULTS: Brain temperature decrease measured by MRSI was -1.7 ± 0.8°C and by phase-mapping -1.8 ± 0.9°C (n = 9) at the end of cooling. Spatial distribution of temperature changes was relatively uniform. Rectal temperature decreased by -0.5 ± 0.3°C (n = 5). The physiological parameters were stable and no shivering was reported. The volunteers remained alert during cooling and no cognitive dysfunctions were apparent in the MMSE test. Postcooling nasal examination detected increased nasal secretion in nine of the ten volunteers. Volunteers' acceptance of the method was good. CONCLUSION: Both MR techniques revealed brain temperature reductions after 60 min of intranasal cooling with balloons circulated with saline at 20°C in awake, unsedated volunteers.