The effects of exercise on serum potassium levels

In view of the significant influence of potassium on the heart, a decision was made to study the effect of exercise on this important ion in two exercise groups of different intensity. The first group consisted of 44 individuals with known coronary artery disease participating in a supervised cardiac rehabilitation program while the other consisted of 30 healthy joggers. Postexercise mean potassium levels were higher in both groups than resting baseline values. In addition, 5 of 44 participants in the coronary artery disease group experienced major potassium increases of 0.9 mmol/L or more while 7 of 30 healthy joggers experienced this magnitude of increase. Remaining unanswered is the question of whether such abrupt rises in potassium levels in this subset of patients alter their vulnerability to cardiac rhythm and conduction disturbances. A question is also raised as to whether rapid return of potassium levels to baseline postexercise contributes to any risks.

Potassium and calcium intake, excretion, and homeostasis in blacks, and their relation to blood pressure

Blacks in the United States have higher blood pressures than whites. They ingest and excrete less calcium and potassium. There is some evidence that blacks have a difference in vitamin D metabolism that might increase any problem caused by low calcium intake. Some studies can be interpreted to suggest that calcium or potassium therapy has greater hypotensive effects in blacks than in whites. Decreased intake of calcium and potassium may be major causes of the greater prevalence of hypertension in blacks than in whites.

Medical and financial implications of discontinuing a statewide free insulin program involving 3,720 people

In 1981 a statewide program supplying free insulin to 3,720 patients of state health clinics was discontinued. We attempted to assess whether this action had an adverse effect medically and financially on those concerned. A computer randomized sample of 351 patients (9%) was studied by personal interview and questionnaire. Information obtained focused on certain events that occurred 18 months before and after the program ceased. Measurements used to determine medical impact were number of hospitalizations, emergency room and physician visits, changes in weight and glucose levels, and episodes of ketoacidosis. Financial impact was measured by cost of hospitalization and physician visits. Our results revealed no significant changes in any of the medical parameters studied except for fasting serum glucose levels above 300 mg/dl, which occurred less frequently after the free insulin program was discontinued. There were fewer hospitalizations, more visits to physicians, and no change in number of emergency room visits after discontinuance of the free program. The overall cost saving was estimated to be +883,558 for the 18-month study period, in addition to the +550,000 the plan had been costing the state.

Laser endarterectomy: a comparison of thrombotic potential following CO2 laser vs surgical endarterectomy

Although laser endarterectomy has recently been suggested as useful in the treatment of arteriosclerotic obstructions, the "in vivo" clotting effects have not been well delineated. In this study, the common carotid and femoral arteries of ten mongrel dogs were exposed, and alternating 1 cm segments of each artery were treated with surgical endarterectomy and low-powered CO2 laser endarterectomy. Segments were then harvested, and subjected to histologic examination and vascular prostacyclin synthesis determinations, as measured by 6-keto PFG1a radioimmunoassay. Gross examination and light and scanning electron microscopy showed increased platelet aggregation and more extensive damaging of the underlying media of the laser compared to the surgical segments. Six-keto PFG1a levels were significantly lower (p = 0.001) in the laser compared to surgical sites (mean 232 +/- 72 pg/mg vs 515 +/- 144 pg/mg), or controls (895 +/- 337 pg/mg). These findings suggest that laser endothelial evaporation leads to increased thrombotic potential in the early post-operative period in comparison to surgical endarterectomy.

The effects of morphine, nalbuphine, and butorphanol on adrenergic function in canine saphenous veins

Saphenous vein rings mounted in organ chambers containing Krebs-Ringer solution were used to determine if the venodilator effects of morphine, nalbuphine, and butorphanol are the result of interference with adrenergic neurotransmission or are caused by direct depressant actions on venous smooth muscle cells. Morphine (5 X 10(-5) M and 2 X 10(-4) M) caused a dose-dependent depression of the contractile response to transmural electrical stimulation. H1- and H2- histamine antagonists did not attenuate the inhibitory effect of morphine. Concentrations of morphine and nalbuphine lower than 5 X 10(-5) M had no effect, whereas 5 X 10(-6) M butorphanol significantly depressed the evoked tension response to electrical stimulation. The contractile responses of the veins to exogenous norepinephrine (NE) were not altered by morphine, indicating a presynaptic site of action rather than a direct action on the venous smooth muscle. Transmural electrical stimulation was used to evoke release of endogenous NE. Morphine (5 X 10(-5) M and 2 X 10(-4) M), nalbuphine (2 X 10(-4) M), and butorphanol (4 X 10(-6) M) significantly decreased release of NE. Naloxone did not alter NE release and did not attenuate the inhibition of NE release observed with the opiates, indicating that the effect of morphine on this neuroeffector junction is not mediated by a naloxone-sensitive opiate receptor. Blockade of presynaptic alpha receptors by phenoxybenzamine or phentolamine augments NE release caused by transmural electrical stimulation; morphine inhibited this augmentation. The results of these experiments indicate that high concentrations of morphine may decrease NE release, an effect that may contribute to the venodilation and hypotension observed following administration of high doses of morphine in humans. In the usual analgesic doses, the venodilatory effects of morphine cannot be explained by local action on either NE release or venous smooth muscle contractility.

Determination of morphine in cerebrospinal fluid and plasma by high-performance liquid chromatography with electrochemical detection

Two methods for the extraction of morphine from cerebrospinal fluid or plasma with quantitation by high-performance liquid chromatography with electrochemical detection were compared for accuracy, precision and ease of preparation. One procedure was a standard extraction procedure and the other utilized a commercially available liquid-liquid extraction column. Both methods produced linear calibration curves over the concentration range of 1-200 ng/ml with coefficients of correlation of 0.999. Since the electrochemical detector is capable of detecting 20 pg of morphine, biological samples as small as 0.1 to 0.4 ml can be quantified with an average relative precision of 4.1 +/- 3.9% over the concentration range 1-200 ng/ml. The potential clinical importance of the assay is demonstrated using a time course distribution study of morphine in the cerbrospinal fluid and plasma of a Rhesus monkey.

A case-comparison study of hypertension and hyperparathyroidism

The frequency of hypertension in patients with primary hyperparathyroidism has been compared with that found in cases matched for conditions of comparable surgical magnitude, age, race, sex, and days in the hospital. The mean blood pressure of the patients was 143/89 mm Hg, significantly higher than that of controls, which was 130/81 mm Hg (P less than 0.001 for systolic and diastolic pressures). The difference was especially notable in view of the fact that the mean weight of the controls was 169 lb compared to 153.9 lb for the patients. Actual hypertension, defined as a diastolic blood pressure of 90 mm Hg or more and or treatment with hypertensive therapy was much more frequent in the patients (90 of 124; 73%) than in the controls (53 of 124; 43%; P less than 0.001). Serum creatinine was 1.3 mm/dl in patients and 1.1 mm/dl in controls. The blood pressure difference between patients and controls persisted when patients with creatinine levels of 2.0 mm/dl or less were omitted. The blood pressure difference between patients and controls had disappeared by the end of hospitalization. We conclude that primary hyperparathyroidism is associated with modest blood pressure elevation, that renal damage is probably not the mechanism, and that surgical cure perhaps may lower blood pressure. The mean effect of primary hyperparathyroidism is to shift the blood pressure distribution curve to the right by approximately 15/10 mm Hg.

Weight, urinary electrolytes and blood pressure--results of several community based studies

One hundred and seventy-nine Negro females, originally seen in high school in 1965, were visited at home during the summers of 1968 or 1969, and were revisited at home during 1978 or 1979. Weight, blood pressure, and urinary electrolyte excretion rates were obtained during the 1968-1969 studies. This report relates the previous measurements to the current (follow-up) blood pressure levels. 52 of the 179 have been told by a physician that they have high blood pressure, and 16 are now taking antihypertensive medication. The group now on medication were 27 lbs heavier and had higher blood pressures, 123/76 vs 114/70 in 1968-1969 than the remainder of the cohort, and their 24-hr urinary sodium excretion rate was greater, 5.9 vs 4.4 mEq/hr (p = 0.06). Among the groups now on therapy, the overnight K rate and Na/Ca ratio were inversely related to the 1968-1969 diastolic BP and the 24-hr Na rate and Na/K ratio were positively correlated with the 1968-1969 blood pressure, both systolic and diastolic. These associations were diminished when partial correlation coefficients adjusted for weight were calculated. Similar associations were not observed among the remainder of the cohort, suggesting that among persons who have the propensity to become hypertensive, the influence of factors which may produce hypertension such as sodium and/or obesity is more easily discernible.

Epidural morphine following epidural local anesthesia: effect on ventilatory and airway occlusion pressure responses to CO2

The authors measured the minute inspired ventilation (VI) and airway occlusion pressure (P 100) responses to CO2 during rebreathing in ten patients who were given epidural morphine for analgesia following lower extremity or lower abdominal surgery. All patients were studied and blood samples for morphine analysis were obtained at four different times: preoperatively, postoperatively premorphine, and one and six hours after a single 10-mg epidural dose of preservative-free morphine in 10 ml of saline. All patients reported effective analgesia with a duration ranging from 8-25.5 h. There were no differences between the pre- and postoperative VI vs. PCO2 and P100 vs. PCO2 response slopes, indicating that the epidural local anesthetic alone had no effect on respiratory drive. Administration of 10 mg morphine epidurally caused a significant 22 per cent decrease in the average VI vs. PCO2 slope and a 33 per cent decrease in the average P100 vs. PCO2 slope one hour postmorphine when compared to the postoperative slopes. The average decrease in VI vs. PCO2 at 6 h postmorphine was not significant. The average P100 vs. PCO2 response slope was decreased significantly at 6 h postmorphine by 27 per cent. There was no significant correlation between serum morphine concentration and the ventilatory responses. The authors conclude that morphine administered by the epidural route produces decreased respiratory drive and that there is a high degree of individual variability in the magnitude and time course of this effect.

Prepregnant blood pressure, hypertension during pregnancy, and later blood pressure of mothers and offspring

In a community-based prospective study of black women, blood pressure (BP) before the onset of the first pregnancy was significantly higher in participants who were eventually diagnosed as having pre-eclampsia than those not so diagnosed. The diagnosis of "pre-eclampsia" appeared to be based entirely on BP; "hypertension associated with pregnancy" is probably a more accurate term. The BP of the pre-eclamptic group was consistently higher before admission to h ospital, during hospitalization, and at 6 weeks and 9 years after delivery. Daughters of pre-eclamptic mothers had higher BP than those of non-pre-eclamptic mothers; this difference was not apparent in boys. The data are compatible with a sex-limited subset of essential hypertension. It is perhaps estrogen-dependent, manifesting itself as mild "pre-eclampsia" in the mother and mild BP elevation in female offspring.

Prepregnant blood pressure, hypertension during pregnancy, and later blood pressure of mothers and offspring

In a community-based prospective study of black women, blood pressure (BP) before the onset of the first pregnancy was significantly higher in participants who were eventually diagnosed as having pre-eclampsia than those not so diagnosed. The diagnosis of "pre-eclampsia" appeared to be based entirely on BP; "hypertension associated with pregnancy" is probably a more accurate term. The BP of the pre-eclamptic group was consistently higher before admission to h ospital, during hospitalization, and at 6 weeks and 9 years after delivery. Daughters of pre-eclamptic mothers had higher BP than those of non-pre-eclamptic mothers; this difference was not apparent in boys. The data are compatible with a sex-limited subset of essential hypertension. It is perhaps estrogen-dependent, manifesting itself as mild "pre-eclampsia" in the mother and mild BP elevation in female offspring.

Urinary electrolytes, body weight, and blood pressure. Pooled cross-sectional results among four groups of adolescent females

Results of blood pressures (BP) and urinary electrolyte excretion studies are reported among several groups of adolescent and young adult females, both black and white, who were initially examined in high school and restudied at home 3--4 years later. Pooling of the data from the several cross-sectional studies (n = 662) revealed a weak but statistically significant positive correlation systolic blood pressure (SBP) and the urinary sodium (Na) excretion rate. Three of four correlations between SBP and potassium (K) were of an inverse nature. Although not statistically significant in their own right, when coupled with the Na/K excretion ratio, which was significantly associated with SBP, a moderating role for K is suggested. The urinary Na, K, and creatinine (Cr) excretion rates were highly intercorrelated and were correlated with weight. As measured by R2 in a stepwise regression analysis, weight contributed approximately 3% to the BP variance, and the urinary electrolytes accounted for approximately 2% of the SBP variance. Statistically significant partial correlation coefficients between SBP and Na, and Na/K, remained after adjusting for body weight.

Urinary electrolytes, body weight, and blood pressure. Pooled cross-sectional results among four groups of adolescent females

Results of blood pressures (BP) and urinary electrolyte excretion studies are reported among several groups of adolescent and young adult females, both black and white, who were initially examined in high school and restudied at home 3--4 years later. Pooling of the data from the several cross-sectional studies (n = 662) revealed a weak but statistically significant positive correlation systolic blood pressure (SBP) and the urinary sodium (Na) excretion rate. Three of four correlations between SBP and potassium (K) were of an inverse nature. Although not statistically significant in their own right, when coupled with the Na/K excretion ratio, which was significantly associated with SBP, a moderating role for K is suggested. The urinary Na, K, and creatinine (Cr) excretion rates were highly intercorrelated and were correlated with weight. As measured by R2 in a stepwise regression analysis, weight contributed approximately 3% to the BP variance, and the urinary electrolytes accounted for approximately 2% of the SBP variance. Statistically significant partial correlation coefficients between SBP and Na, and Na/K, remained after adjusting for body weight.

Humidity in children and adults using the controlled partial rebreathing anesthesia method

The authors examined inspired humidity using a controlled partial rebreathing anesthesia method (CPRAM) and a circle system in 16 healthy adults and five healthy children. The patients were divided into five study groups (A-E). All patients except those in Group E were anesthetized with fentanyl, pancuronium, nitrous oxide-oxygen, 66-33 per cent, and their lungs were mechanically ventilated; patients in Group E received halothane and nitrous oxide-oxygen, 66-33 per cent, with spontaneous ventilation. Group A (five children) had inspired hummidity measured within a modified coaxial (Bain) anesthesia circuit using CPRAM. Groups B and C (five adults each) had humidity measured within the modified coaxial circuit and at the end of a non-modified coaxial circuit using CPRAM. Groups D and E (three adults each) had humidity measured in the semi-closed and closed circle systems, respectively. Initial, mid-, and end-inspired humidity were measured in all groups for two hours by interrupting the controlled ventilation at 30-min intervals, except in patients of Group E, who had humidity measured at similar intervals for two hours during spontaneous ventilation. No significant difference was found among initial, mid-, or end-inspired humidity, nor was there a significant difference between inspired humidities in children and in adults using CPRAM. The humidity measured in adults within the circuit near the endotracheal tube was not significantly different from that measured distal to the fresh gas flow. The humidities in all CPRAM patients exceeded those of both the semiclosed and closed circle systems, stabilizing within 30 min and remaining constant between 24 and 26 mg H2O/1.

Spontaneous-ventilation general anesthesia for outpatients using enflurane

We have described our technique for general anesthesia for outpatients using a mixture of nitrous oxide, oxygen, and enflurane with spontaneous ventilation through a Bain anesthetic circuit. In our experience, surgical excision of impacted teeth, multiple extractions and alveoloplasty, enucleation of simple cysts, excision of benign tumors, and other similar operations have been done efficiently with these anesthetic techniques. More than 500 such cases have been managed without significant complication. The concepts of selection and preparation of patients, airway security and protection during surgery performed in the upper airway on an unconscious patient who is breathing spontaneously, continuous monitoring of vital functions, and rapid induction and recovery all combine to make this technique consistent with standards for excellence in anesthesia.

Reactions of mothers with mentally retarded children: a social perspective

38 mothers of retarded children and 70 mothers of nonretarded children were asked a series of Likert-type questions designed to tap social behaviors and attitudes. The mothers of retarded children were more likely to express positive attitudes toward the retarded and to expect that the “average” person in the community has a negative opinion of the retarded than were the mothers of the nonretarded children. Mothers of retarded children also manifested different patterns of social behavior regarding employment and utilization of babysitters, in comparison with mothers of nonretarded children.

An evaluation of enflurane combined with nitrous oxide as an amnesic agent for outpatient oral surgery

Nitrous oxide has been added to a technique for anesthesia, allowing the concentration of enflurane to be reduced by a third while retaining the amnesic properties, stable physiologic parameters, rapid recovery, and excellent acceptance by the patient.

Alleged inner ear trauma: compensation pending

The English literature on the incidence of nystagmus in normal subjects and in patients with head and/or neck injuries is reviewed. The authors present a series of 202 patients with alleged vestibular trauma. The incidence of spontaneous and positional nystagmus would seem to be no greater in patients with alleged vestibular trauma than that found in the normal subjects, suggesting that these patients do not have objective evidence of vestibular trauma. Objective criteria for diagnosing vestibular abnormalities by electronystagmography are presented. At least 22% of a series of 2408 patients were found to have a functional hearing loss. The importance of looking for functional overlay in patients involved in litigation cases is stressed.

An evaluation of enflurane as an amnesic agent for outpatient oral surgery

An alternative to general anesthesia for outpatient oral surgery that creates a state of cooperative amnesia without eliminating the patient's protective reflexes has been developed. Enflurane, 1.5%, administered via a nasal mask produced a high incidence of amnesia with all patients remaining cooperative, with protective reflexes intact.

Massive myoglobinuria precipitated by halothane and succinylcholine in a member of a family with elevation of serum creatine phosphokinase

Massive myoglobinuria developed in a patient given halothane and IV succinylcholine, Marked elevations of serum CPK were found in the patient and several family members. Myopathic changes in electromyogram and lack of neuromuscular symptoms and physical findings prompted the diagnosis of familial nonprogessive muscular dystrophy. Other hereditary muscular diseases were eliminated by medical workup. It is recommended that patients with known myopathy or unexplained elevations of serum CPK not receive the combination of halothane and succinylcholine.

Electrolytes, environment and blood pressure

1. Studies to explain a significant socioeconomic and rural-urban blood pressure gradient found in central Mississippi are reported.

2. 24 h sodium excretion alone fails to explain the differences found, and fails to correlate with blood pressure.

3. A single 24 h determination of electrolyte excretion correlates modestly with the mean of 6 days' collection. Three days' collection and blood pressure determination is a reasonable compromise.

4. The urinary Na/Ca ratio is significantly higher in specimens from rural black girls compared with urban girls, and significantly higher in specimens from those with systolic pressure > 125 mmHg compared with those with < 105 mmHg pressure.

5. The urinary Na/K ratio of black girls was significantly higher than that of white girls of the same age, as was their blood pressure.

6. No correlation between blood pressure and urinary electrolytes could be found in black women aged between 35 and 45.

Use of the Edwards Personal Preference Schedule with delinquents

To determine if EPPS scores differentiate institutionalized delinquent and nondelinquent adolescents scores of 49 delinquent boys and 46 delinquent girls, age range 15 to 19 yr., were compared with scores of comparable nondelinquent groups. Delinquent boys scored significantly lower in Achievement, Deference, Affiliation, and Dominance. Delinquent females scored higher in Heterosexuality and lower in Endurance and Deference. Incomplete description of presumed need constellations in delinquency and inconsistency in male and female results obtained with the EPPS makes questionable the use of this instrument for the stated purpose.