Coronary perfusion pressure during cardiopulmonary resuscitation after spinal anesthesia in dogs

Cardiac arrest during spinal anesthesia is a rare event, but when it does happen cardiopulmonary resuscitation (CPR) is often ineffectual. This study examines the effect of spinal anesthesia on coronary perfusion pressure (CPP) during CPR and the subsequent response of CPP to epinephrine administration. Twenty mongrel dogs were anesthetized, and randomly assigned to a spinal injection with either 0.5 mg/kg bupivacaine or with an equivalent volume of normal saline. Twenty minutes later, ventricular fibrillation was electrically induced and after 1 min CPR was started. CPP was measured every minute. After 4 min of CPR, epinephrine 0.01 mg/kg was given followed by 0.1, 0.2, and 0.4 mg/kg epinephrine intravenously (IV) at 6, 8, 10 min of CPR, respectively. The bupivacaine (n = 11) group had significantly less CPP than the sham spinal (n = 8) group, 12-13 mm Hg as compared to 27-34 mm Hg. Only 4/11 dogs (36%) in the bupivacaine group had CPP > or = 15 mm Hg during the first 4 min after arrest as compared to 8/8 (100%) in the sham spinal group. This increased to 7/11 dogs (64%) after 0.01 mg/kg epinephrine and to 9/11 after 0.1 mg/kg epinephrine. Total spinal anesthesia decreases CPP and thus the efficacy of CPR in dogs below the threshold previously established for predicting successful resuscitation. Epinephrine is effective in increasing CPP during CPR above the critical threshold. These data suggest that if cardiac arrest occurs during spinal anesthesia, epinephrine should be given in doses of 0.01-0.02 mg/kg IV initially and then increasing to 0.1 mg/kg IV. When this does not work, and ineffective CPR is suspected, alternative resuscitative measures should be considered.

Helminths in Rattus norvegicus captured in Chunchon, Korea

We report helminthic infections in the liver and intestine of Rattus norvegicus captured in Chunchon, Korea from April to October, 1994. Out of 43 examined rats, eggs of Capillaria hepatica were found in 11, Hymenolepis diminuta in 14 and Taenia taeniaeformis metacestodes in 28. Those rats can be sources of zoonotic infections in the surveyed area.

Hydrostatic versus oleic acid-induced pulmonary edema: high-resolution computed tomography findings in the pig lung

RATIONALE AND OBJECTIVES

We evaluated the differences between combined hydrostatic and hypervolemic edema and oleic acid-induced edema on high-resolution computed tomography (HRCT) scans.

METHODS

Twelve anesthetized and ventilated pigs were studied. Hydrostatic edema was induced by ligation of the abdominal aorta and infusion of normal saline (n = 4); permeability edema was induced by intravenous injection of oleic acid (n = 4). Four pigs were studied as normal controls. Serial scans were obtained before and after induction of edema at a constant position in the caudal lobe of the lung. The distribution of edema was assessed visually. Cross-sectional areas (CSAs) of the pulmonary artery and vein were measured both at the lobar and segmental levels.

RESULTS

Gravity-dependent opacity, peribronchovascular fluid collection, prominent centrilobular core, thickening of the interlobular septa, and air-space consolidation at the dependent site were the sequential HRCT findings of hydrostatic edema. Randomly distributed, diffuse patchy high attenuation areas with a tendency for predilection in the subpleural and peripheral areas of the secondary lobule were the findings of oleic acid-induced edema. Hydrostatic edema increased the mean CSAs of the lobular vein by 137.8% +/- 78.7, but oleic acid edema decreased the mean CSAs by 33.2% +/- 22.7. Changes in the mean CSAs of the pulmonary arteries were not significant. The mean vein-to-artery ratio increased significantly in hydrostatic edema but decreased in oleic acid edema.

CONCLUSION

HRCT findings for hydrostatic and oleic acid-induced pulmonary edema differed both in distribution of edema and in pulmonary vascular response.

Design and performance of a trickling air biofilter for chlorobenzene and o-dichlorobenzene vapors

From contaminated industrial sludge, two stable multistrain microbial enrichments (consortia) that were capable of rapidly utilizing chlorobenzene and o-dichlorobenzene, respectively, were obtained. These consortia were characterized as to their species composition, tolerance range, and activity maxima in order to establish and maintain the required operational parameters during their use in biofilters for the removal of chlorobenzene contaminants from air. The consortia were immobilized on a porous perlite support packed into filter columns. Metered airstreams containing the contaminant vapors were partially humidified and passed through these columns. The vapor concentrations prior to and after biofiltration were measured by gas chromatography. Liquid was circulated concurrently with the air, and the device was operated in the trickling air biofilter mode. The experimental arrangement allowed the independent variation of liquid flow, airflow, and solvent vapor concentrations. Bench-scale trickling air biofilters removed monochlorobenzene, o-dichlorobenzene, and their mixtures at rates of up to 300 g of solvent vapor h(-1) m(-3) filter volume. High liquid recirculation rates and automated pH control were critical for stable filtration performance. When the accumulating NaCl was periodically diluted, the trickling air biofilters continued to remove chlorobenzenes for several months with no loss of activity. The demonstrated high performance and stability of the described trickling air biofilters favor their use in industrial-scale air pollution control.

Evaluation of finger blood flow with Tc-99m MDP (methylene diphosphonate)

BACKGROUND

A variety of methods were used to establish objective diagnostic criteria of Raynaud's phenomenon. We intended to introduce another method, using radionuclide (Tc-99m methylene diphosphonate) scintigraphy, which is more objective, simple and economical than the past methods.

METHODS

The finger blood flow with radionuclide scintigraphy was evaluated in 10 patients of Raynaud's syndrome, 12 patients of connective disease without Raynaud's symptoms, and 20 normal persons. After immersing one hand in ice water (4 degrees C) for 30 seconds, the hand was exposed to 22 degrees C room air for 15 minutes, and then the patients received the intravenous (IV) bolus of 20 microCi of Tc-99m methylene diphosphonate (MDP). At the same time, scintigraphic image of both hands started with the region of interest, including the second, third, fourth and fifth fingers distal to the metacarpophalangeal (MCP) joints. Computer recording of the counts in the region of interest every 2 seconds for 310 seconds was started on IV bolus injection.

RESULTS

The 310 seconds cumulative digital blood flow ratio of cold exposed hand to room air exposed hand was significantly lower in Raynaud's group (p < 0.001), and the ratio of initial slope of activity curve was also lower in the Raynaud's group (p < 0.001). Of the 8 patients showing Raynaud's syndrome, 4 patients of scleroderma and 1 patient of multiple myeloma showed no improvement of finger blood flow in the cold exposed hand after 2 weeks of pharmacological therapy, but 1 patient of mixed connective tissue disease, 1 patient of Behcet's syndrome and 1 patient of SLE showed much improved finger blood flow after combined administration of vasodilator, calcium channel blockers and antiplatelet drugs.

CONCLUSIONS

The evaluation of finger blood flow with 99mTc-MDP could be considered to be one of the simple, economical and new methods that can be used in the follow-up, objective assessment of therapeutic effect, and giving an aid in the study of the pathophysiology of the Raynaud's phenomenon.

The Influence of Phenylephrine-Induced Hypertension During Focal Cerebral Ischemia on the Formation of Brain Edema

The authors investigated the effects of phenylephrine-induced hypertension on the development of cerebral edema and neuronal dysfunction during focal cerebral ischemia. Mean arterial pressure was increased by 25-30 mm Hg immediately after middle cerebral artery occlusion (MCAO) in anesthetized rats. The increase was maintained for 3 h, at which time the brains were harvested and sectioned along coronal planes spanning the distribution of the MCA. The specific gravity (SG) was determined in specimens of cortex and subcortex. Brain sections adjacent to those used for SG measurement were incubated in 2,3,5-triphenyltetrazolium (TTC). There was edema formation in both groupsipsilateral to MCAO. However, in some regions, there was less edema accumulation in the induced hypertension group than in normotensive control animals. In adjacent regions, the area of reduced or absent TTC staining was also significantly less in the induced hypertension group. The data indicate that, in this model, induced hypertension established soon after the onset of ischemia can serve to reduce the area of histochemically detectable neuronal dysfunction, and that not only is edema formation not aggravated, but it is actually reduced.

A comparison of the cerebral and haemodynamic effects of mannitol and hypertonic saline in an animal model of brain injury

There has recently been an increased interest in the use of hypertonic saline solutions in the fluid resuscitation of trauma victims and to control intracranial hypertension. In this study, the cerebral and haemodynamic effects of a 3.2% hypertonic saline solution were compared with those of either a 0.9% saline or 20% solution were compared with those of either a 0.9% saline or 20% mannitol solution in a rabbit model of brain injury. Forty-five minutes following the creation of a left hemispheric cryogenic brain lesion, equal volumes of hypertonic saline, 0.9% saline, or mannitol were infused over a 5 minute period. Monitored variables over the ensuing 120 minutes included mean arterial pressure, central venous pressure, intracranial pressure, hematocrit, serum osmolality and oncotic pressure. Upon conclusion of the two hour study period, hemispheric water contents were determined by the wet/dry weight method. There were no significant differences in mean arterial pressure between the three groups at any point during the experiment. Plasma osmolality was significantly increased by 10-11 mOsm/kg in both the mannitol and hypertonic groups. The infusion of either mannitol or hypertonic saline produced a transient decrease in intracranial pressure lasting approximately 60 minutes whereas animals in the saline group demonstrated a continual increase in intracranial pressure. The lesioned hemisphere demonstrated a significantly greater water content than the non-lesioned hemisphere.

Phenylephrine-induced hypertension reduces ischemia following middle cerebral artery occlusion in rats

We studied the influence of phenylephrine-induced hypertension on the area of ischemia during brief middle cerebral artery occlusion. Rats were anesthetized with 1.2 minimal alveolar concentration (MAC) isoflurane, and the middle cerebral artery was occluded via a subtemporal craniectomy. Immediately thereafter, in one group (n = 9) arterial blood pressure was increased 30-35 mm Hg above the preocclusion level by intravenous infusion of phenylephrine. In a second, control, group (n = 10) there was no manipulation of blood pressure. Local cerebral blood flow was determined autoradiographically 15 minutes after occlusion. The areas (expressed as a percentage of the total coronal cross-sectional area) in which local cerebral blood flow decreased to three ranges (0-6 ml/100 g/min [rapid neuronal death probable], 6-15 ml/100 g/min [delayed neuronal death probable], and 15-23 ml/100 g/min [electrophysiologic dysfunction with prolonged survival probable]) were measured. The areas in which local cerebral blood flow decreased to the two more severely ischemic ranges were smaller in the phenylephrine group than in the control group. For example, in the coronal section in the center of the middle cerebral artery distribution, local cerebral blood flow was 0-6 ml/100 g/min in 6.7 +/- 1.4% of the section in normotensive rats but was in that range in only 1.7 +/- 0.6% of the section during phenylephrine-induced hypertension (p less than 0.05). For the 6-15 ml/100 g/min range, the areas were 6.8 +/- 0.8% and 3.8 +/- 0.7%, respectively (p less than 0.05). For the 15-23 ml/100 g/min range, there were no differences between groups.(ABSTRACT TRUNCATED AT 250 WORDS)

Epidemiological characteristics of ketoacidosis among Korean diabetic patients

An epidemiological study on diabetic ketoacidosis (DKA) was done by analysis of 207 cases collected from the medical records of 6 major general hospitals in Seoul area during the period of 5 years between 1979 and 1984. There was female predominance in the occurrence of DKA (male/female ratio, 0.71) in spite of the male predominance in general prevalence of diabetes mellitus (1.80). This female predominance in DKA was most striking in the age group under 40. There was a significant seasonal variation in the occurrence of DKA. DKA occurred most frequently in colder season with the highest peak in December. In July and August, the hottest season in Korea, not even a single case of DKA was recorded in this series. No discernible precipitating factor was found in 39.3% of DKA cases and infections was present as a cause of DKA in 30% of cases. In 27.5%, DKA was the first clinical presentation of diabetes and in the remainders of cases, diabetes was known to be present for average of 6.4 years. Mortality of DKA was 13.2% in this series. As to the socioeconomic status, the education level, the style of living and the duration of diabetes, there were not ascertainable differences between the DKA cases and other diabetic cases. The prospective epidemiological study of diabetic population in Korea, especially in female group, would be necessary for elucidation of the characteristics of DKA in Koreans such as the female predominance and the seasonal difference of the occurrence.

Linkage of faded gene (fe) to chromosome 6 of the mouse

Linkage tests on the faded gene were carried out with some coat color and biochemical markers, It was shown that the faded locus was not closely linked to the following loci: Idh-1 (chromosome 1), a (2), Car 2 (3), Mup-1 (4), Pgm-1 (5), Hbb (7), Gpi-1 (7), Es-1 (8), Trf (9), Es-3 (11), s (14), Sod-1 (16) and Ce-2 (17). The mutant locus showed linkage with Ggc on chromosome 6.

Faded, a mutation in the KSB strain of mouse which shows age-related pigment changes

Mice with a strange coat color were found in the KSB strain and separated as KSB-fe after fixation for this gene. These mutant mice have faded coat color (black becomes gray), with white underfur, the pigment changing towards white accompanied by frequent skin lesions. Faded homozygotes show a loss of pigment granules with ageing. Genetic studies were conducted with mice bearing this faded coat color. The mode of inheritance of the faded coat color was established to be autosomal recessive and the name faded (fe) was proposed. Faded was not allelic to dilute (d), leaden (ln), beige (bg) or pink-eyed dilution (p) loci.

High cervical spine and craniocervical junction injuries in fatal traffic accidents: a radiological study

Postmortem radiographic examinations in 312 victims of fatal traffic accidents were analyzed with respect to injuries to the cervical spine. Most fractures and dislocations in this group were found to involve the craniocervical junction and the upper two cervical segments. Over half were flexion injuries, one-fifth caused predominantly by extension. Flexion and extension views were found to be helpful in demonstrating the instability of many injuries.

Efficacy of computed tomography of the abdomen--early results

Our experience with 153 CT scans of the abdomen and pelvis over the first eight months of availability at our institution has been analyzed. The efficacy in terms of contribution to the diagnosis in each patient was assessed and accuracy determined. CT was found to have made a significant contribution to the diagnosis in patients with diseases of the pancreas, aorta, retroperitoneal structures, and in cases of abdominal and pelvic masses and abcesses. It has been somewhat less helpful in evaluation of liver and renal diseases. Overall, CT scanning appears to be a significant new diagnostic modality in the evaluation of patients with abdominal and pelvic diseases.

Traumatic vertebral arteriovenous fistula associated with cervical spine fracture

A case of a traumatic vertebral arteriovenous fistula associated with a high cervical fracture-dislocation is reported. The fistula was not suspected clinically but was fortuitously diagnosed by brachial arteriography carried out for a deteriorating level of consciousness. The patient's complex injuries were managed by conservative treatment of the fracture-dislocation and later by ligation of the proximal and distal vertebral artery for trapping of the fistula. The indications and the various surgical procedures for the treatment of vertebral arteriovenous fistula are discussed. The report emphasizes the value of cerebral angiography in head and neck injuries.

Postmortem radiology of head neck injuries in fatal traffic accidents

A series of 146 victims of fatal traffic accidents were subjected to postmortem radiographic examination prior to medicolegal autopsy. A total of 42% were found to have radiographically demonstrable head injuries ranging from relatively simple linear skull fractures to massive skull damage. Free intracranial or intravascular air was demonstrated in more than 60%. A total of 21% had demonstrable neck injuries, most of which were localized to a single level at the craniocervical junction or the upper two cervical vertebrae. Flexion and extension studies of this area are of major importance in demonstrating the injury and locating potentially occult lesions for the forensic pathologist.