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S Bragg

Publications and source records attributed to S Bragg.

7 recordsLinked to original sources
PubMed1987

Neurologic benefits from the use of early cardiopulmonary resuscitation.

The efficacy of bystander CPR in resuscitation from cardiac arrest when defibrillation is available within five to six minutes has been questioned. Epidemiologic studies from different cities have shown conflicting results. We conducted a study to determine the effect of early CPR versus no CPR on resuscitability, 24-hour survival, and neurologic deficit in an animal model of cardiac arrest. Twenty-two mongrel dogs were subjected to five minutes of electrically induced ventricular fibrillation. In 11 dogs, closed-chest massage and ventilation with room air was begun immediately and was continued for five minutes. The other 11 dogs received no CPR. At five minutes defibrillation was attempted and advanced cardiac life support (ACLS) protocols were followed until the animal was resuscitated or died. No statistical difference in resuscitability or 24-hour survival between the two groups was demonstrated. Eight of 11 "early CPR" animals were resuscitated and survived 24 hours; six of 11 "no CPR" dogs were resuscitated, and five lived for 24 hours. A significant difference was demonstrated by the Student t test in neurologic deficit and ease of resuscitation. "Early CPR" dogs had no neurologic deficit, while "no CPR" dogs had a 41% deficit (P less than .01). "Early CPR" dogs were resuscitated in significantly less time once ACLS was started (29 versus 317 seconds), and required less electrical energy (100 versus 560 J), fewer countershocks (1.3 versus 4.0), and less epinephrine (0.1 versus 1.7 mg) than did "no CPR" animals. In this animal model of cardiac arrest, early CPR was shown to be beneficial to neurologic function and ease of resuscitation, even when ACLS was provided within five minutes.

Animals↗
PubMed1987

Comparison of epinephrine and phenylephrine for resuscitation and neurologic outcome of cardiac arrest in dogs.

A study was done comparing resuscitability and 24-hour neurologic outcome in fibrillating dogs that were treated with either phenylephrine (a primary alpha agonist) or epinephrine. Ventricular fibrillation was induced electrically in 18 dogs. After three minutes, standard CPR was instituted using a mechanical resuscitator. Dogs were given phenylephrine or epinephrine at nine minutes and defibrillation was attempted at 12 minutes. Dogs underwent hemodynamic monitoring and pharmacologic support, if necessary, for an additional 90 minutes. At four, eight, 12, and 24 hours, a standard neurologic examination was performed and deficit scores were assigned by an observer blinded to the drug given. Fourteen of the 18 dogs were resuscitated. There were no statistically significant differences in the epinephrine- or phenylephrine-treated groups with regard to number of animals resuscitated, time and interventions required for resuscitation, initial cardiac rhythm post resuscitation, or occurrence of ventricular fibrillation during resuscitation. No differences were found in arterial, central venous, or myocardial perfusion pressures during CPR. Phenylephrine-treated dogs tended to have higher mean pressures in the critical care period (15 to 30 minutes), although this was not significant. Total neurologic deficit scores were 127.8 +/- 83.8 for the phenylephrine-treated group and 129.4 +/- 87.4 for the epinephrine group. No significant differences were found in the level of consciousness, cranial nerve function, motor skills, or general behavior scores. We conclude that there is no difference in neurologic or cardiovascular outcome when phenylephrine is compared to epinephrine in a canine model of cardiac arrest and cardiopulmonary resuscitation.

Animals↗
PubMed1985

Expired PCO2 as an index of coronary perfusion pressure.

Presently, there is no reliable noninvasive method of assessing the adequacy of cardiopulmonary resuscitation (CPR). Studies of animals have shown that during prolonged arrest the coronary perfusion pressure (CPP) is correlated with successful resuscitation. During previous studies it appeared that expired PCO2 correlated with CPP. To investigate this relationship, eight mongrel dogs (mean weight, 22.7 +/- 5.8 kg) were anesthetized with pentobarbital. Catheters were placed in the thoracic aorta and right atrium of each dog. Each animal was electrically fibrillated, and CPR was started using mechanical resuscitator. The PCO2 was determined at end expiration using a Hewlett Packard 47210A Capnometer with the electrode attached to the endotracheal tube. After 10, 15, 20, or 25 minutes of ventricular fibrillation and closed-chest massage, a thoracotomy was performed, and internal massage was begun. Coronary perfusion pressure was calculated at least each minute and correlated with the PCO2 values. A correlation coefficient of 0.78 was calculated based on 368 data points for eight dogs (P less than 0.01). The results of this study indicate that expired PCO2 is positively correlated with CPP in the canine model of CPR. Inasmuch as CPP correlates with survival in prolonged CPR, the noninvasive measurement of PCO2 may be a useful method of assessing the adequacy of CPR.

Animals↗
PubMed1985

Expired PCO2 as a prognostic indicator of successful resuscitation from cardiac arrest.

We performed a study to determine if the measurement of expired PCO2 during CPR for cardiac arrest could be used as a prognostic indicator of successful resuscitation. Twelve mongrel dogs were fibrillated electrically, and external chest massage and assisted ventilation were applied for 15 minutes. Expired PCO2 and aortic and right atrial pressures were monitored each minute of arrest. Coronary perfusion pressure (CPP) was calculated by subtracting the right atrial from the aortic diastolic pressure. Half the dogs received high-force chest compression (80 lb) and half received low-force chest compression (40 lb). The six dogs that received high-force compression were resuscitated successfully. The expired PCO2 was significantly higher in the successfully resuscitated dogs (expired PCO2 = 9.6 +/- 3.2 mm Hg) when compared to those dogs that died (expired PCO2 = 3.2 +/- 1.1 mm Hg, P less than .01). Expired PCO2 was highly correlated (r = 0.91, P less than .01) with the CPPs. The measurement of expired PCO2 during attempted CPR may be useful as a noninvasive indicator of CPP and adequate technique. Further studies on the use of this technique as an assessment criterion are warranted.

Animals↗
PubMed1985

Importance of the duration of inadequate coronary perfusion pressure on resuscitation from cardiac arrest.

The effect of the duration of inadequate coronary perfusion pressure on resuscitation from cardiac arrest was examined in 32 mongrel dogs with a mean weight of 22 +/- 5 kg. In all dogs, the heart was electrically fibrillated and closed chest compression with assisted ventilation was performed for 15 minutes. At this time, all dogs had an inadequate coronary perfusion pressure (mean 7 +/- 9 mm Hg) and were randomized to a control group (group 1) with continued closed chest compression or to one of the three groups with open chest cardiac massage. These three groups differed only in the duration of continued closed chest compression before initiation of open chest massage (15, 20 and 25 minutes, respectively, in groups 2, 3 and 4). The control group (group 1) had no significant increase in coronary perfusion pressure, and only one of the eight dogs could be resuscitated. The three groups with open chest cardiac massage had a significant increase in coronary perfusion pressure (from 5 +/- 9 to 51 +/- 26 mm Hg, p less than 0.05), but the rate of successful resuscitation depended on the duration of inadequate coronary perfusion pressure before cardiac open chest massage. In group 2, six of eight dogs were resuscitated (p less than 0.05 compared with the control group); in group 3, three of eight dogs were resuscitated and in group 4 none of the eight dogs was resuscitated. The resuscitation rate was significantly (p less than 0.05) greater in group 2 than in group 4. These findings indicate that techniques that improve coronary perfusion pressure during cardiopulmonary resuscitation must be applied before extensive myocardial cellular dysfunction occurs if the probability of successful resuscitation is to be improved.

Animals↗
PubMed1985

Developing a rating interview guide.

Nursing administrators have spent considerable time and effort developing various interview tools that will meet the needs of the institution, however, of equal importance is the method of evaluating responses obtained during the interview process. This article discusses a master tool designed as a base from which a variety of interview tools can be developed. Weighted scoring reflects the strengths of the applicant consistent with the position requirements and in an equitable manner.

Administrative Personnel↗