Diagnosis of major peripheral arterial trauma by transcutaneous oxygen monitoring

During a 6 month period, 36 consecutive suspected major peripheral arterial injuries in 33 patients were evaluated by clinical examination and Doppler signal. Thirty-three of these injuries were also evaluated using portable transcutaneous oxygen monitors. Of the 12 confirmed arterial injuries, 2 had normal Doppler-derived blood pressures and significantly decreased transcutaneous oxygen tensions. The transcutaneous oxygen values in traumatized limbs with arterial injury were significantly lower than in traumatized limbs without arterial injury (34 +/- 6 versus 58 +/- 3, p less than 0.01). The ratio of the injured limb transcutaneous oxygen tension to the uninjured contralateral limb transcutaneous oxygen tension was also significantly lower in the group with arterial injury than in the group without arterial injury (0.72 +/- 0.08 versus 1.12 +/- 0.05, p less than 0.01). The overall sensitivity and specificity of the diagnosis of major peripheral arterial injury by a bilateral transcutaneous oxygen ratio less than 0.90 was 80 percent and 91 percent, respectively. In addition, transcutaneous oxygen monitoring helped quantify tissue perfusion in limbs with decreased neurologic function and Doppler-derived blood pressure. The results suggest that transcutaneous oxygen monitoring is a valuable, noninvasive adjunctive method for the diagnosis of major peripheral arterial trauma.     

Metabolic factors in the control of energy stores

We have examined some of the factors involved in the control of food intake and integrated the data using methods of systems analysis from biomedical engineering. The central hypothesis is that energy stored in the body is a regulated variable. Alterations in the quantity of stored calories initiates changes designed to restore the store of calories to its original level. These responses are both short-term and long-term in nature. They involve integrating data on the quantities of protein, carbohydrate, and lipid stores in the body, probably through such feedback signals as amino acids, glucose, glycerol, and free fatty acids.     

Role of anaerobic bacteria in subdural empyema: Report of four cases and review of 327 cases from the english literature

Anaerobic bacteria were isolated from the subdural space in all four cases of subdural empyema encountered over a $\text{2}\text{1}\text{2}$ year period. Only one aerobe was isolated in these cases. The bacteriology of subdural empyema was further analyzed from a review of 327 cases reported in the English literature. Anaerobes accounted for 12 per cent of 234 cases. In addition, 27 per cent of cases were reportedly “sterile.” These data support our finding that anaerobic bacteria may play a far more important role in subdural empyema than was previously appreciated.     

Some respiratory and metabolic effects of exercise in moderately obese men.

The effects of varying levels of exercise on oxygen uptake, CO2 production, blood pressure, arterial blood gasses, and arterial concentrations of glucose, insulin, and growth hormone were examined in ten normal weight and ten moderately overweight young men. At comparable external work loads with a bicycle ergometer, the lean men required less oxygen than the obese men. When oxygen uptakes were matched during exercise on a treadmill, the lean men were walking on a steeper grade or at a higher rate than the obese men. The efficiency of exercise as assessed by the relation between oxygen uptake and work did not differ between the two groups. Blood pressure rose more in the obese during exercise than in the lean. The fall in lactate and rise in bicarbonate was of greater magnitude during cycle ergometry than during treadmill exercise. Obese and lean men, however, showed similar changes. With each level of exercise, there was a fall in arterial insulin levels, but the concentrations in the blood of overweight men always remained significantly above that of the normal men. Growth hormones tended to be higher in the normal weight men, but the differences were usually not significant, and there was no significant rise with exercise in either group until the highest levels of work were achieved. Glucose concentrations tended to be higher in the obese men, but fell to constant levels in both groups during exercise. Blood pressure rose to a greater extent in the overweight men during exercise.     

Intravenous terbutaline and simultaneous β1-blockade for advanced premature labor

Seventeen patients in advanced premature labor (cervical dilatation ≥3 cm and effacement ≥50%) were randomized in a double-blind protocol to receive metroprolol (a β₁-adrenergic antagonist) or a placebo in conjunction with intravenous and oral terbutaline (a β₂-agonist) in an attempt to inhibit the side effects of terbutaline. Both groups of patients had a dose-related increase in heart rate and systolic blood pressure and a decrease in diastolic blood pressure. Laboratory studies revealed significant hyperglycemia, hypokalemia, hypocalcemia, and acidosis during the intravenous terbutaline infusion, all of which normalized during oral terbutaline therapy. There were no significant differences in the cardiovascular or metabolic responses to terbutaline between the metroprolol and placebo patients. The mean delay in delivery was 5.7 days, with 59% of patients having delivery delayed for 48 hours or more. The mean prolongation time was shorter, but not statistically significant, for those patients receiving metroprolol. Despite the use of high-dose terbutaline, there were no significant complications of therapy. There was little efficacy of infusion dosages above 40 μg/min or repeated courses of intravenous tocolysis. Although recent reports do not recommend tocolysis in these patients, this study suggests that combined β-mimetics and glucocorticoids may be the optimal care for patients in advanced premature labor, in particular, those with infants of very low birth weight.     

Compositional and metabolic changes in brown adipose tissue following a single test meal

In rats maintained on a scheduled feeding plan, the hypertrophy of brown adipose tissue (BAT) observed after a low-protein/high-carbohydrate single test meal was accompained by significant changes in the percentage of all major constituents of the tissue. There was a fall in the percentage of water (P < 0.01), a rise in the percentage of fat (P < 0.05), and a rise in the percentage of glycogen (P < 0.001). The largest absolute changes following a meal were in the fat content, which almost doubled, and in the glycogen content, which exhibited about a four-fold increase. Deposition of fat in the BAT following the test meal was accompanied by a three-fold increase in the rate of fatty acid synthesis (P < 0.05). The in vitro respiration rate of BAT was usually significantly increased in the meal-fed rats, but the effect of replacing the protein content of the test meal with starch was not clear. A lower protein, higher starch diet (9% of calories from protein, 72% from starch) resulted in a trend for a larger thermic effect than a higher protein, lower starch diet (27% of calories from protein, 54% from starch).     

Massive bile pertonitis in infancy due to spontaneous bile duct perforation with portal vein occlusion.

A case of massive bile peritonitis due to spontaneous slough of the junction of the cystic, common, and common hepatic ducts in a 5-wk-old male infant is reported. This was managed successfully by a Roux-en-Y jejunal anastomosis to the remnant of common hepatic duct. Subsequent ascites (4 mo postoperatively) was relieved by peritoneovenous drainage by a Holter valve from the peritoneal cavity to the right atrium. Comments are made relative to an etiologic commonality between spontaneous perforation of the bile ducts in infancy, “congenital” choledochal cyst, and biliary atresia and a possible role for birth-acquired viral infection, particularly with a herpes type of virus, in these disorders.     

Acute diaphragmatic injuries

A 5-year experience with 43 patients with acute diaphragmatic injuries is reviewed. Thirty-three of the patients had penetrating trauma, and 10 suffered blunt trauma. All but 1 of the patients had associated intraabdominal trauma. Fifteen had traumatic diaphragmatic hernia at the time of operation. The operative approach was uniformly through the abdomen. Mortality and morbidity were directly related to the number of associated organs injured.Chest roentgenograms in 26 of the 43 patients were interpreted as suspicious or diagnostic of diaphragmatic injury when presented as unknowns to fully trained radiologists, but only 7 of these were originally so interpreted.Delay in operation was a significant contributing factor to morbidity, particularly in patients with thoracic stab wounds. Guidelines suggested to prevent delay include: (1) increased awareness of the possibility of acute diaphragmatic injury, (2) careful evaluation of the plain chest roentgenogram and liberal use of appropriate contrast studies when indicated, (3) prompt repair of recognized diaphragmatic injuries, (4) laparotomy as the operative approach in the acute injury, and (5) appropriate contrast studies after recovery from massive thoracoabdominal trauma and prior to hospital discharge.     

Continuous transcutaneous oxygen monitoring during an intraoperative cardiac arrest

A transcutaneous oxygen sensor was used continuously during surgical management of a ruptured abdominal aortic aneurysm. Closed chest compression initiated for intraoperative cardiac arrest gave an inadequate cardiac output on the basis of falling PtcO2 despite transmitted femoral pulses and an excellent PaO2. This discordance provided a rationale for open cardiac massage, which increased the cardiac output and tissue perfusion (PtcO2) needed for successful resuscitation. The PtcO2 sensor provides immediate, non-invasive, and continuous information regarding tissue oxygenation. It reflects the PaO2 in hemodynamically stable patients as well as providing a sensitive indicator for inadequate cardiac output during shock. In patients undergoing cardiopulmonary resuscitation, a falling PtcO2 with an acceptable PaO2 indicates poor tissue perfusion and, in select circumstances, may warrant open cardiac massage.