PubMed Health⌕ Search

Biomedical subjects

J H Modell

Publications and source records attributed to J H Modell.

At least 37 records · Page 2Linked to original sources
PubMed1983

Continuous positive airway pressure improves oxygenation in dogs after the aspiration of blood.

Fourteen dogs were anesthetized, intubated, and breathed room air spontaneously. We then instilled 2 ml/kg of fresh nonheparinized donor blood into their tracheas. Seven dogs received no treatment and served as controls (group A); respiratory rate (RR) increased from 25 +/- 11 (mean +/- SD) to 103 +/- 33 breath/min, HR decreased from 179 +/- 28 to 136 +/- 42 beat/min, PaO2 decreased from 82 +/- 10 to 30 +/- 4 torr, pulmonary venous admixture (Qsp/Qt) increased from 0.14 +/- 0.10 to 0.72 +/- 0.06, and venous oxygen tension (PVO2) decreased from 46 +/- 4 to 22 +/- 5 torr 10 min after the aspiration of blood; all changes were statistically significant (p less than .05). After 4 h, RR and HR returned to control values, but PaO2 was only 58 +/- 10 torr. Cardiac output, oxygen consumption (VO2), and pulmonary and systemic BP and resistances were not significantly affected. Thirty-five min after the other 7 dogs aspirated blood (group B), 10 cm H2O of continuous positive airway pressure (CPAP) was applied while they breathed spontaneously. CPAP reduced Qsp/Qt to 0.31 +/- 0.10 and 0.15 +/- 0.11 30 and 90 min after its application, respectively (p less than .05). By 4 h, the PaO2 of group B dogs was 81 +/- 15 torr (p less than .05 compared with group A). CPAP also increased arteriovenous oxygen content difference (C[a-v]O2) compared with the nontreated dogs. Four hours after the aspiration of blood, all dogs were extubated. Twenty-four hours later, arterial blood gases were normal in all dogs of both groups.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1981

Positive end-expiratory pressure (PEEP) and cerebrospinal fluid pressure during normal and elevated intracranial pressure in dogs.

The effect of up to 15 cm H2O positive end-expiratory pressure (PEEP) on cerebrospinal fluid pressure (Pcsf) was investigated in five anaesthetised, mechanically ventilated dogs during normal and then elevated (40-50 cm H2O) intracranial pressure (ICP). Stepwise elevations of PEEP in 5 cm H2O increments resulted in small rises in Pcsf at normal ICP and in significantly larger rises when ICP was elevated. The regression equations for the relationships between Pcsf and end-expiratory pressure (EEP) were as follows: Pcsf = 12.95 + 0.82 EEP for normal ICP, and Pcsf = 46.41 + 2.06 EEP for elevated ICP. Mean PaCO2 rose from 39.7 +/- 2.5 to 47.6 +/- 5.0 torr during normal ICP, and from 34.2 +/- 2.9 to 50.9 +/0- 5.3 torr at elevated ICP as PEEP was elevated to 15 cm H2O. We conclude that PEEP raised Pcsf, and that this increase is more severe under conditions of elevated ICP. The rise in Pcsf due to PEEP may be explained by either the rise in intrathoracic pressure or the rise in PaCO2, or both.

Animals↗
PubMed1980

Near-drowning: correlation of level of consciousness and survival.

This paper reports a retrospective review of 121 cases of near-drowning treated at university hospitals in Miami and Gainesville. The series included 57 adults and 64 children who were classified into three categories, Category A (Awake), Category B (Blunted) and Category C (Comatose), based on their level of consciousness on arrival at the primary hospital. Results based on the total 121 patients showed 87 per cent survived with apparently normal brain function, two per cent survived with impaired brain function and 11 per cent died. The survival rate of all patients who were awake when they entered the hospital was significantly greater than that of both those who were admitted and blunted consciousness (p = 0.05) and those who were comatose when admitted (p less then 0.0001). Further, the group whose members had blunted consciousness had a significantly greater number of normal survivors than the group whose members were comatose on admission (p less than 0.002). All treated adults survived without permanent neurological damage and only three surviving children in the series suffered residual brain damage. Whether the course of the seven patients, three adults and four children, who died without return of brain function, would have been altered by deliberate attempts to preserve the brain is a matter of speculation.

Adult↗
PubMed1978

Evaluation of criteria for discontinuing mechanical ventilatory support.

Thirty-three patients who required short-term postoperative mechanical ventilatory support were studied to compare different criteria established to initiate weaning from mechanical ventilation. Intermittent mandatory ventilation criteria (i.e., decreasing mechanical respirator rate as long as the arterial (pHa) remains above 7.35) and conventional criteria (ie, vital capacity greater than 15 ml/kg and peak negative pressure greater than 20 cm H2O) were compared to determine which would more rapidly predict a patient's ability to sustain total spontaneous respiration. All patients were eventually weaned from mechanical ventilation and had their tracheas extubated. Twenty-one patients maintained a pHa of greater than 7.35 during total spontaneous ventilation before they would, or could, meet conventional criteria for initiating a trial of spontaneous respiration (P less than .001). Seven patients simultaneously met both criteria for maintaining total spontaneous ventilation and the remaining five patients met conventional criteria before intermittent mandatory ventilation criteria. In the latter group, the pHa decreased below 7.35 during spontaneous respiration but in only one patient did it fall below 7.30. Our findings suggest that a patient's ability to maintain a pHa of greater than 7.35 while decreasing the frequency of mechanical ventilator breaths is more accurate than peak negative pressure and vital capacity for predicting ability to sustan adequate spontaneous respiration.

Adolescent↗
PubMed1978

Biology of drowning.

The near-drowning victim must be treated immediately for ventilatory insufficiency, hypoxia, and the resulting acidosis. The cause and pathophysiologic changes of pulmonary insufficiency vary, depending on the tpe and volume of fluid aspirated. Success or failure of the overall resuscitative effort frequently depends on the adequacy of prompt emergency resuscitation and on effective intensive pulmonary care. Each patient should be evaluated and treated individually, since abnormalities of multiple organ systems can occur, their degree and form varying considerably from patient to patient (28).

Acid-Base Equilibrium↗
PubMed1977

Near drowning.

Explore the source record for details and available documents.

Blood Gas Analysis↗
PubMed1977

Respiratory aspiration of stomach contents.

The aspiration of stomach contents is a common clinical problem of concern to all physicians. Its consequences are varied, depending on the amount and distribution of the aspirate, its pH, and the presence or absence of food, particulate matter, and bacteria. Because multiple factors are involved, aspiration of stomach contents can lead to several distinct syndromes of pulmonary injury, all of which unfortunately have been labeled "aspiration pneumonitis." We review the pathophysiology of each of these syndromes and discuss important diagnostic and therapeutic consequences.

Adrenal Cortex Hormones↗
PubMed1976

Liquid ventilation of primates.

Three adult monkeys were anesthetized with ketamine and ventilated with fluorocarbon liquid [perfluoro bis (1, 4-isopropoxy) butane (Caroxin-D)] at 1 atmosphere on two separate occasions. During five runs, liquid ventilation was continued for 60 minutes. The sixth run was continued for ten minutes. Arterial blood gas levels during and after liquid ventilation were adequate for survival. Three years after the first period of liquid ventilation, the animals were killed. Approximately 0.001 mg of fluorocarbon per gram of tissue was present in the kidney, liver, brain, spleen, muscle, and heart. Fat contained approximately seven to nine times this amount, and the lung and pulmonary lymph nodes contained approximately 1,000 times this amount. In no case was it clinically evident that the monkeys had undergone periods of liquid ventilation. We conclude that primates can be ventilated successfully with liquid fluorocarbon on at least two separate occasions and can return to breathing air without obvious deleterious effects, but fluorocarbon is retained in small amounts for at least three years.

Adipose Tissue↗
PubMed1976

Clinical course of 91 consecutive near-drowning victims.

Hospital records of 91 consecutive near-drowning victims were studied retrospectively. Eight-one (89 percent) of these patients survived. Patients who were alert on arrival at the emergency room survived, but those who were comatose and had fixed dilated pupils died. Other states of consciousness were unreliable predictors of survival. All patients with a normal chest roentgenogram on admission survived; however, values for arterial oxygen tension (PaO2) did not necessarily correlate with the chest roentgenograms. Values for arterial blood gas tensions and pH varied widely, as follows; PaO2, 25 to 465 mm Hg; arterial carbon dioxide tension (PaCO2), 17 to 100 mm Hg; pH, 6.77 to 7.50; and arterial bicarbonate level, 6.6 to 29.7 mEq/L. The ratio of PaO2 to the fractional concentration of oxygen in the inspired gas (FIo2), which was calculated to standardize PaO2 data for varying concentrations of inspired oxygen, ranged from 30 to 585 mm Hg. Only one patient with a ratio of PaO2/FIo2 greater than 150 mm Hg on admission subsequently died; this was a neurologic rather than a pulmonary death. Serum electrolytic concentrations and values for hemoglobin level and hematocrit reading neither predicted survival nor indicated that a threat to life existed. Steroid and prophylactic antibiotic therapy did not appear to increase the chance of survival. Observations on these patients are discussed in light of previous experiments in animals, and an approach to therapy is suggested.

Adolescent↗
PubMed1975

Treatment of chronic pain with acupuncture.

We performed 979 acupuncture treatments in 261 patients with chronic pain. A substantial number of patients stated that they had relief immediately following a series of four acupuncture treatments. It did not matter whether the needles were placed in the traditional meridian locations of in arbitrary fixed control points. Four weeks following treatment, 65% of the patients reported little or no reduction in the intensity of their pain, 17% reported a 50% reduction, and 18% at least a 75% reduction.

Acupuncture Therapy↗