Enalaprilat improves systemic and mesenteric blood flow during resuscitation from hemorrhagic shock in dogs.

We investigated the systemic and mesenteric cardiovascular effects of administering enalaprilat during resuscitation from hemorrhage. Dogs were hemorrhaged (mean arterial pressure [MAP] 40-45 mmHg for 30 min, then 30-35 mmHg for 30 min) and were then resuscitated with intermittent lactated Ringer's solution (200 mL/kg/h during first 40 min, and 60 mL/kg/h during the following 130 min, MAP 75-80 mmHg). A constant-rate infusion of saline with or without enalaprilat (0.

Enalaprilat improves systemic cardiovascular parameters and mesenteric blood flow during hypotensive resuscitation from hemorrhagic shock in dogs.

Resuscitative interventions that improve mesenteric perfusion without causing instability in systemic arterial pressures may be helpful for improving trauma patient outcomes. Blocking angiotensin II formation with enalaprilat may be such an intervention. Two questions were addressed in this two-part study investigating resuscitation from hemorrhagic shock in dogs: Can systemic arterial pressures be maintained while administering a constant rate infusion of enalaprilat during resuscitation, and can enalaprilat improve cardiovascular status during resuscitation? Animals were hemorrhaged to a mean arterial pressure (MAP) of 40 to 45 mmHg for 30 min and then 30 to 35 mmHg for 30 min.

Monitoring gastrointestinal intraluminal PCO2: problems with airflow methods.

Unlabelled: Gastrointestinal intraluminal PCO2 (PiCO2) information is used to assess the adequacy of trauma patient resuscitation and to assist in choosing resuscitative interventions. Therefore, determining the limitations and potential caveats of different PiCO2 monitoring systems is clinically important. This study compared two PCO2 monitoring systems.

Blood cholesterol screening influence of fasting state on cholesterol results and management decisions.

Objective: To compare fasting and nonfasting total and high-density lipoprotein (HDL) cholesterol values in adults and to determine how closely classification into risk groups for coronary heart disease based on nonfasting blood tests compares with classification based on fasting studies.

Design: Cross-sectional study.

Setting: A community hospital general internal medicine clinic.

Missed injuries in pediatric trauma.

Missed injuries in trauma continue to be a nemesis to the trauma surgeon. Missed injuries in adult trauma patients range in frequency from 9 to 28 per cent, with some being life threatening or permanently disabling. We report the incidence of missed injuries in pediatric trauma to be 20 per cent, in our retrospective review of 107 severe pediatric trauma patients.

Bystander Trauma Care training in Iowa.

Objective: The Iowa Bystander Trauma Care program trained citizens to provide initial care at the scene of a motor vehicle crash. The development, implementation, and evaluation of the program are described.

Methods: The National Highway Traffic Safety Administration's curriculum was used as the basis for developing the Iowa Bystander Trauma Care program.

Continuous dose furosemide as a therapeutic approach to acute respiratory distress syndrome (ARDS).

Background: Acute respiratory distress syndrome (ARDS) is seen in a variety of clinical settings in critically ill patients. ARDS has been defined as a clinical syndrome characterized by progressive hypoxemia, tachypnea, and generalized patchy bilateral pulmonary infiltrates in the absence of cardiac failure. Furosemide has been shown to improve pulmonary gas exchange and intrapulmonary shunt in animal models of ARDS by preferential perfusion of nonedematous lung units.

Descriptive ethics and neuroleptic dose reduction.

Topic: Descriptive ethics and related concepts of beneficence, justice, and autonomy.

Purpose: To provide a framework to aid in decision making when neuroleptic drugs are decreased in a vulnerable elderly population.

Source: A clinical situation is used to illustrate the ethical issues considered in neuroleptic drug reduction.

The efficacy of laparoscopic examination of the internal inguinal ring in children.

The ability of physicians to identify a patent processus vaginalis by laparoscopic examination of the internal ring is now well established, but the efficacy on patient outcome is not. The authors reviewed their experience to determine the effect of diagnostic laparoscopy of the internal ring on the management of children with inguinal hernias. The records of 150 children who underwent inguinal surgery were reviewed--75 before (group 1) and 75 after (group 2) pediatric laparoscopy was introduced into the authors' practice.

Does the duration of N2O administration affect postoperative nausea and vomiting?

Nausea and vomiting are the most frequent postoperative complications in the ambulatory surgical setting. In the present study, data were obtained from 184 adult ambulatory cosmetic surgery patients to determine if the use of nitrous oxide (N2O) was associated with an increased incidence of postoperative nausea and/or vomiting (PNV). Anesthesia was induced with thiopental and maintained with an opioid (fentanyl or sufentanil) and isoflurane with or without N2O.

Blood pressure and neurogenic adaptations to reduced dietary sodium in the SHR model of hypertension.

Sodium (Na) balance is maintained by a complex set of genetic, hemodynamic, hormonal and neural mechanisms that affect intake, reabsorption and excretion. This research focused on the role of a reduction in dietary Na on cardiovascular and neuroeffector function in normotensive (WKY) and spontaneously hypertensive rats (SHR) raised from 5-20 weeks on a control Na diet (12 mmol per 100 g food) or various low Na diets (0.5-2 mmol per 100 g food).

Why the phantom p-wave during general anesthesia?

Although atrioventricular junctional rhythm (AVJR) is frequently encountered during general anesthesia, its genesis is poorly understood. The present study was undertaken to test the hypothesis that AVJR is promoted by hypocarbia. One hundred patients (69 females, 31 males), ASA Physical Status Class I, who were 20 to 30 years old, were studied.

Risks associated with dietary sodium reduction in the spontaneous hypertensive rat model of hypertension.

Sodium balance is maintained by a complex set up of hemodynamic, hormonal and neural mechanisms that affect intake, reabsorption and excretion. The focus of the following research was on the cardiovascular and neuroeffector effects of dietary Na reduction primarily in normotensive Wistar-Kyoto (WKY) and spontaneously hypertensive rats (SHR) raised from 4 to 15 weeks on a control Na diet (CNa: 12 mmol per 100 g food) or various low Na diets (LNa: 0.5 to 3 mmol per 100 g food).

Left ventricular mass and fluid compartmentalization in Wistar-Kyoto and spontaneously hypertensive rats fed high- or low-sodium diet.

Our purpose was to test the hypothesis that a high sodium intake promotes fluid volume expansion, and hence weight gain, in the left ventricle. Between 6 and 30 weeks of age, Wistar-Kyoto (WKY) and spontaneously hypertensive rats (SHR) were fed low-, control- or high-sodium chow. After treatment, known quantities of 22NaCl and Na2(35)SO4 were injected intravenously into each animal and permitted to equilibrate with body fluids in order to measure sodium and sulphate spaces in various tissues.

Left ventricular function of the isolated, genetically obese rat's heart.

We sought to determine if left ventricular (LV) function of the heart from the adult, chronically obese animal is impaired. Hearts from 50 wk-old genetically obese female Zucker rats (624 +/- 13 g) and their lean littermate controls (275 +/- 5 g) were isolated during ether anesthesia, supported metabolically by retrograde aortic perfusion (6 ml/min, 35 degrees C) with physiological solution containing suspended canine erythrocytes (hematocrit, 20%), and the ventricles were paced at 180 beats/min. A distensible, fluid-filled balloon was placed in the LV, and pressure-volume (PV) relationships were obtained.

O2 reserve of left ventricle of isolated, saline-perfused rabbit heart.

The heart from the pentobarbital-anesthetized rabbit was isolated, and a fluid-filled balloon was placed in the left ventricular chamber for assessment of isovolumic pressure development. The bicarbonate-buffered, physiological perfusate was aerated initially with 95% O2-5% CO2, and then progressive decreases in arterial O2 content (CaO2) were produced in a stepwise fashion by substituting N2 for O2 in the aerating gas mixture. If, for a specified set of experimental conditions, no change in ventricular function occurred after the initial decrease in CaO2, it was concluded that the heart was oxygenated adequately prior to the first CaO2 decrement.

Ouabain-induced mechanical toxicity: aberrations in left ventricular function, calcium concentration, and ultrastructure.

The isolated rabbit heart was employed to determine if the myocardial mechanical dysfunction (mechanical toxicity) produced by digitalis was accompanied by ultrastructural lesions and an excessive accumulation of calcium by the cardiac cell. Ouabain (1.2 or 2.

Criteria for adequate oxygenation of isometric kitten papillary muscle.

Papillary muscles were taken from the right ventricles of hearts excised from chloroform-anesthetized kittens. Progressive 100-mmHg stepwise decreases in superfusate oxygen partial pressure (PO2) from control (95% O2 aeration, PO2, 620-650 mmHg) were produced, and subsequent changes in isometric active and resting tension were measured. If, under a given set of experimental conditions, the initial decrement in PO2 produced no decrease in active tensions development, it was concluded that complete oxygenation of the entire muscle cross section was achieved when bath PO2 was maximal.

Magnesium net fluxes and distribution in rabbit myocardium in irreversible contracture.

Distribution of magnesium (Mg) in heart muscle was studied by measuring fluxes of Mg and transmembrane potentials as a function of perfusate [Mg2+] after a massive increase in permeability of the sarcolemma was induced in the Langendorff prepared heart from the Nembutal-anesthetized rabbit. After onset of 0 mM [Ca2+] perfusion which produced excitation-contraction (E-C) uncoupling and mechanical arrest, action potentials recorded from subepicardial cells showed an increase in duration and decrease in amplitude, which progressed until no transmembrane potentials could be observed. Restoration of physiological salt solution perfusion after 15 min of [Ca2+]-free perfusion caused an irreversible contracture that was associated with 1) efflux of potassium (K) and myoglobin, 2) perfusate [Mg2+]-dependent flux of Mg, and 3) transmembrane potentials of 0 mV.

Effect of nitroglycerin with and without systemic hypotension on canine regional myocardial tritiated water deposition.

A marked alteration in the transmural distribution of left ventricular blood flow, with a relative increase in subendocardial and mid-wall flows, but with no change in the distribution of the relative blood flow to the two ventricles occurred when nitroglycerin was administered and the systemic arterial blood pressure in the upper body maintained near control levels in anaesthetized, open-chested dogs. The relative increase in subendocardial and mid-wall flows may have resulted from a direct action of nitroglycerin on the coronary vasculature. On the other hand, the intravenous administration of nitroglycerin, when followed by the hypotension which it produces, did not alter the transmural distribution of blood flow in the left ventricle of the dog.

K+ and Mg-2+ net fluxes in relation to zero [Ca-2+] perfusion and subsequent cardiac contracture.

Following within 45 sec after the development of contracture induced by restoring normal ionic composition perfusion conditions after a 12 min period of mechanical arrest in the rabbit heart caused by zero [Ca-2+] perfusion, there is an explosive efflux of K+ and Mg-2+. After shorter periods of Ca-2+-lack arrest, the restoration of [Ca-2+] to normal causes recovery of rhythmic contraction and no K+ efflux. The K+ and Mg-2+ effuxes are ascribed to the effects of the contracture itself and not simply to the loss of Ca-2+ during zero [Ca-2+] arrest nor to the restoration of normal perfusate [Ca-2+], except insofar as the latter operates to induce the contracture.