SURGICAL EMERGENCIES

Action according to preconceived plans may be life-saving at the scene of accidents involving serious injury to several persons. Severe hemorrhage and respiratory obstruction must be dealt with immediately. As the latter may not be apparent at a glance, it should be looked for specifically. Artificial respiration may be necessary. Spinal puncture is a procedure in first aid which should be carried out at the site of an accident if there are symptoms of cerebral edema or of increased cerebral pressure.Routine plans should be laid to meet the emergency of cardiac arrest on the operating table. The surgeon must be prepared to begin cardiac massage within three minutes in such instances.     

LARYNGOSPASM FROM THE ANESTHESIOLOGIST'S VIEWPOINT

Laryngeal spasm is a problem constantly confronting the anesthetist. It can be serious and may produce fatal cerebral or cardiac complications. Etiologic agents include primary vagal hypertonicity, anoxemia, and painful stimulation of whatever source.Laryngeal spasm must be differentiated from simple obstruction by the tongue or foreign bodies, epiglottic impaction, laryngeal edema, tracheal spasm and collapse, and bronchial spasm.Proper checking of the patient before anesthesia and adequate premedication with atropine or scopolamine are preventive measures of great value. Once spasm has developed the etiologic agent should be removed if possible. Other measures include intravenous administration of atropine or curare, tracheal intubation, and tracheotomy.     

Medical Care of the Alcoholic Patient

Alcoholism is an illness that constitutes a major health problem at all levels of society. The physician should accept his responsibility to prevent it and to care for the alcoholic. If he knows that one of his patients is drinking immoderately, he should warn him of the outlook. A patient''s acquired dependence on alcohol may be overt, or revealed only on examination for organic disease or emotional disturbance. The diagnosis may be accepted reluctantly, or denied despite positive evidence, but the patient should be persuaded to give up drinking. He may require psychiatric help or advice from a social worker. He may be so ill as to require treatment in hospital, and hospitals must recognize the urgency of such admissions. Discharge from hospital does not end treatment, for alcoholism is a chronic disease, requiring long-term planning, persistent follow-up and enduring sympathy by the physician, who must always be as available to his alcoholic patient as he is to his patient with diabetes, epilepsy or cardiac disease.     

Lightning Injury: Two Case Histories and a Review of Management

Two cases of fatal lightning injury are described. Fixed dilated pupils should not be taken as an indicator of death after a lightning strike. Persons who fail to breath spontaneously within one minute of lightning shock should receive external cardiac massage and mouth-to-mouth resuscitation. Paralysis may persist as result of cerebral oedema or prolonged hypoxia—it is therefore suggested that adequate ventilation and metabolic balance should be maintained until recovery or death.     

Key issues in managed competition.

All managed competition proposals for health system reform must confront several key issues. The premiums paid to health care purchasing cooperatives will need to be subsidized for those who cannot pay full fare; the amount and sources of the subsidies are controversial political issues. The payments passed on by purchasing cooperatives to health plans must be risk adjusted to account for differences in the health care needs of their enrolled populations. This is essential to create a level playing field for competition and to eliminate incentives for plans to use risk assessment for attracting enrollees. The data and methods needed for risk adjustment, however, are not adequate at present. The Clinton Administration''s plan to limit expenditure increases raises a host of thorny issues. Maintaining quality of care will require health plan quality report cards to be supplemented by external quality assurance systems. Assuring quality will be particularly problematic for traditional indemnity plans. The structure and governance of the system, administration simplification, and other issues need to be addressed. The size and voluntariness of the purchasing cooperatives greatly influence all of these considerations. Physicians should inform their political representatives on how these issues should be resolved as compromise bills are drafted by the United States Congress this year.     

Syncope, cerebral perfusion, and oxygenation.

During standing, both the position of the cerebral circulation and the reductions in mean arterial pressure (MAP) and cardiac output challenge cerebral autoregulatory (CA) mechanisms. Syncope is most often associated with the upright position and can be provoked by any condition that jeopardizes cerebral blood flow (CBF) and regional cerebral tissue oxygenation (cO(2)Hb). Reflex (vasovagal) responses, cardiac arrhythmias, and autonomic failure are common causes. An important defense against a critical reduction in the central blood volume is that of muscle activity ("the muscle pump"), and if it is not applied even normal humans faint. Continuous tracking of CBF by transcranial Doppler-determined cerebral blood velocity (V(mean)) and near-infrared spectroscopy-determined cO(2)Hb contribute to understanding the cerebrovascular adjustments to postural stress; e.g., MAP does not necessarily reflect the cerebrovascular phenomena associated with (pre)syncope. CA may be interpreted as a frequency-dependent phenomenon with attenuated transfer of oscillations in MAP to V(mean) at low frequencies. The clinical implication is that CA does not respond to rapid changes in MAP; e.g., there is a transient fall in V(mean) on standing up and therefore a feeling of lightheadedness that even healthy humans sometimes experience. In subjects with recurrent vasovagal syncope, dynamic CA seems not different from that of healthy controls even during the last minutes before the syncope. Redistribution of cardiac output may affect cerebral perfusion by increased cerebral vascular resistance, supporting the view that cerebral perfusion depends on arterial inflow pressure provided that there is a sufficient cardiac output.     

Severe hypoxaemia with a left ventricular assist device in a minipig model with an undiagnosed congenital cardiac disease

We describe the placement of a left ventricular assist device (LVAD) in a pig with spontaneously occurring atrial septal defect (ASD) (incidental finding) that created a right-left cardiac shunt, with subsequent severe hypoxaemia. Early diagnosis was critical in order to prevent end-organ damage due to hypoxaemia. Adequate monitoring alerted us to the deterioration in oxygenation, haemodynamics and cerebral oxygen metabolism. This forced us to change the level of assistance provided by the pump, and thus dramatically correct this impairment. Necropsy revealed an ostium secundum ASD. In conclusion, if hypoxaemia presents after implementation of an LVAD, the presence of a right-left shunt must be ruled out. The first step must be a judicious reduction in assist device flow to minimize intracardiac shunting. Subsequently, atrial septal closure of the defect should be considered. We report an experimental model of severe hypoxaemia after placement of an LVAD as part of a larger research project.     

Psychiatry in General Practice

Psychiatrists should include the family doctor in their plans for future psychiatric services. The general practitioner now treats most of the patients who seek help for psychiatric disorder and he could not give up his psychiatric practice even if he wanted to. Furthermore, there are not now nor will there ever be enough psychiatrists to take over all patients with mental ills. Most emotionally disturbed patients can be better handled by their family physicians than by a specialist.To provide the best care for emotionally disturbed people the communication between family doctors and psychiatrists must be improved. The specialist must acknowledge the importance of the general practitioner''s role in psychiatric diagnosis and treatment and give him more help. Medical schools must provide better undergraduate and postgraduate psychiatric training for the students who will become family doctors. Health plans and other prepayment agencies should properly compensate the general practitioner for giving psychiatric treatment. The specialist in psychiatry should consult more readily with the general practitioner and help him carry out some of the therapy. General hospitals should permit family doctors to admit mental patients to psychiatric wards in a general hospital and to carry out psychiatric treatment with the help of the specialist in psychiatry.     

Closed-Chest Massage: An Effective Resuscitative Procedure for the Maintenance of the Circulation During Cardiac Arrest

Reports of clinical benefits of closed-chest cardiac resuscitation refute recently published studies contesting its effectiveness.Our experimental investigations demonstrate that closed-chest massage is able to achieve adequate cerebral circulation and oxygenation during cardiac arrest.Clinical studies indicate that a significant number of coronary patients can be saved if a monitor system is used to warn of the onset of ventricular fibrillation or arrest. To be successful, closed-chest resuscitation must be instituted within the four-minute limit after onset of cardiac arrest. When ventricular fibrillation occurs, electrical countershock is usually obligatory. Cardiac pacemaking is a specific necessity for patients with ventricular arrest.     

Measuring dose from radiotherapy treatments in the vicinity of a cardiac pacemaker

This study investigated the dose absorbed by tissues surrounding artificial cardiac pacemakers during external beam radiotherapy procedures. The usefulness of out-of-field reference data, treatment planning systems, and skin dose measurements to estimate the dose in the vicinity of a pacemaker was also examined. Measurements were performed by installing a pacemaker onto an anthropomorphic phantom, and using radiochromic film and optically stimulated luminescence dosimeters to measure the dose in the vicinity of the device during the delivery of square fields and clinical treatment plans. It was found that the dose delivered in the vicinity of the cardiac device was unevenly distributed both laterally and anteroposteriorly. As the device was moved distally from the square field, the dose dropped exponentially, in line with out-of-field reference data in the literature. Treatment planning systems were found to substantially underestimate the dose for volumetric modulated arc therapy, helical tomotherapy, and 3D conformal treatments. The skin dose was observed to be either greater or lesser than the dose received at the depth of the device, depending on the treatment site, and so care should be if skin dose measurements are to be used to estimate the dose to a pacemaker. Square field reference data may be used as an upper estimate of absorbed dose per monitor unit in the vicinity of a cardiac device for complex treatments involving multiple gantry angles.     

MEDICAL PREPAREDNESS FOR DISASTER

The Federal Civil Defense Administration has been consolidated under the President''s Reorganization Plan No. 1 of 1958 with the Office of Defense Mobilization. The new organization, the Office of Civil and Defense Mobilization, should be able to deal more efficiently with the problem of mobilization and management of all resources and production of the nation in time of disaster. As preparation for possible enemy attack, organized plans entailing training, supplies, equipment and communications for use in major peacetime disasters—floods, earthquakes, tornado damage—should be carried forward vigorously. Apathy must be overcome. From the local to the highest level all civil defense and disaster plans must be developed and kept flexible enough to be operable during any kind of emergency.Physicians must learn as much as they can about the mass care of casualties, how to survive under the most trying of circumstances. Drills in dealing with simulated disaster are of utmost importance for finding out ahead of time what must be done and the personnel and supplies needed for doing it.     

HYPOTHERMIA IN CEREBRAL RESUSCITATION

A correlative review of experimental and clinical brain injury was undertaken for the purpose of assessing the therapeutic value of the delayed application of hypothermia in the management of cerebral injury. For any post-injury treatment to be possible, it must be assumed that there is a progressive intrinsic adverse response of the brain to injury for some hours after the actual injury.The value of any therapeutic effort in treating the injured brain remains to be proven, although there is considerable theoretical and indirect clinical evidence to suggest that hypothermia may be a potent tool. Study should be directed toward a clinically applicable technique which would provide means of distinguishing between reversible and irreversible interruption of cerebral function.     

Treatment of the inadequate endometrium in infertility

The one feature that characterizes all shock, regardless of its cause, is a reduction in the effective circulating blood volume. The reduced blood volume leads to decreased venous return, decreased cardiac output, vasoconstriction, tachycardia, hypotension, tissue anoxia and death if the sequence of events is uninterrupted. Immediate therapy must be directed at restoration of the blood volume, preferably with whole blood. Infection must be controlled by use of antibiotics intramuscularly and intravenously. If shock persists, aqueous adrenal extract should be administered in large quantities. As a last resort, a vasopressor should be tried.     

The pregnant woman with heart disease: management of pregnancy and delivery

Women with heart disease are at risk of cardiac complications during pregnancy and delivery. Risk assessment should be performed in these women, and the management of pregnancy and delivery should be planned accordingly. Depending on the risk, women should be cared for in specialised centres, regional centres or a combination of both. Multidisciplinary teams must be involved in the care of these women. Adequate organisation of care and communication between the team members is important to prevent complications.     

Cardiac Exposure in the Dynamic Conformal Arc Therapy,Intensity-Modulated Radiotherapy and Volumetric Modulated Arc Therapy of Lung Cancer

Purpose

To retrospectively evaluate the cardiac exposure in three cohorts of lung cancer patients treated with dynamic conformal arc therapy (DCAT), intensity-modulated radiotherapy (IMRT), or volumetric modulated arc therapy (VMAT) at our institution in the past seven years.

Methods and Materials

A total of 140 lung cancer patients were included in this institutional review board approved study: 25 treated with DCAT, 70 with IMRT and 45 with VMAT. All plans were generated in a same commercial treatment planning system and have been clinically accepted and delivered. The dose distribution to the heart and the effects of tumor laterality, the irradiated heart volume and the beam-to-heart distance on the cardiac exposure were investigated.

Results

The mean dose to the heart among all 140 plans was 4.5 Gy. Specifically, the heart received on average 2.3, 5.2 and 4.6 Gy in the DCAT, IMRT and VMAT plans, respectively. The mean heart doses for the left and right lung tumors were 4.1 and 4.8 Gy, respectively. No patients died with evidence of cardiac disease. Three patients (2%) with preexisting cardiac condition developed cardiac disease after treatment. Furthermore, the cardiac exposure was found to increase linearly with the irradiated heart volume while decreasing exponentially with the beam-to-heart distance.

Conclusions

Compared to old technologies for lung cancer treatment, modern radiotherapy treatment modalities demonstrated better heart sparing. But the heart dose in lung cancer radiotherapy is still higher than that in the radiotherapy of breast cancer and Hodgkin’s disease where cardiac complications have been extensively studied. With strong correlations of mean heart dose with beam-to-heart distance and irradiated heart volume, cautions should be exercised to avoid long-term cardiac toxicity in the lung cancer patients undergoing radiotherapy.     

Wildlife conservation planning under the United States Forest Service's 2012 planning rule

In 2012, the United States Forest Service (USFS) promulgated new planning regulations in accordance with the National Forest Management Act (NFMA). These regulations represent the most significant change in federal forest policy in decades and have sweeping implications for wildlife populations. We provide a brief overview of the history of the NFMA planning regulations and their wildlife provisions and review the current science on planning for effective wildlife conservation at the landscape scale. We then discuss the approach to wildlife conservation planning in the 2012 rule and compare it to alternatives that were not selected and previous iterations of the planning rule. The new planning rule is of concern because of its highly discretionary nature and the inconsistency between its intent on the one hand and operational requirements on the other. Therefore, we recommend that the USFS include in the Directives for implementing the rule commitments to directly monitor populations of selected species of conservation concern and focal species and to maintain the viability of both categories of species. Additional guidance must be included to ensure the effective selection of species of conservation concern and focal species, and these categories should overlap when possible. If the USFS determines that the planning unit is not inherently capable of maintaining viable populations of a species, this finding should be made available for scientific review and public comment, and in such cases the USFS should commit to doing nothing that would further impair the viability of such species. In cases where extrinsic factors decrease the viability of species, the USFS has an increased, not lessened, responsibility to protect those species. Monitoring plans must include trigger points that will initiate a review of management actions, and plans must include provisions to ensure monitoring takes place as planned. If wildlife provisions in forest plans are implemented so that they are enforceable and ensure consistency between intent and operational requirements, this will help to prevent the need for additional listings under the Endangered Species Act and facilitate delisting. Although the discretionary nature of the wildlife provisions in the planning rule gives cause for concern, forward-thinking USFS officials have the opportunity under the 2012 rule to create a robust and effective framework for wildlife conservation planning. © 2013 The Wildlife Society.     

Heterogeneity of membrane properties in vascular muscle cells from various vascular beds

It is becoming increasingly more apparent that vascular smooth muscle cannot be treated as a homogeneous group and cannot be compared to other types of smooth muscle at least in terms of responsiveness to vasoactive agents. This heterogeneity may have as part of its basis differences in the molecular structure at the level of the plasma membrane. Such differences manifest themselves in terms of resting membrane potential (Em), response to cardiac glycosides, ionic conductances, and membrane responses to neurotransmitters. Results show that the middle cerebral artery of the cat has a higher Em and depolarizes to excess K+ with a steeper slope than other peripheral arteries of the same animal. Furthermore, cerebral arteries from different areas of the brain exhibit distinctly different resting membrane properties as well as different responses to norepinephrine. In addition, cerebral arteries exhibit a high degree of electromechanical coupling not always observed in other peripheral arteries.     

Site specific differential activation of ras/raf/ERK signaling in rabbit isoproterenol-induced left ventricular hypertrophy

To understand better the mediating role of ras/raf/ERK signaling pathway in development of cardiac hypertrophy and cerebrovascular events in vivo, the molecular mechanism of the pathway in heart and cerebral arteries after isoproterenol (ISO) induced beta-adrenergic receptor (betaAR) stimulation was examined in rabbit as animal model. Compared with the heart, our findings indicate that ISO-stimulation results in increase in mRNA levels of ras, raf, and immediate-early genes in the cerebral arteries. Conversely, the ras and raf protein expression levels (determined by Western blot) and the ras-GTP level (determined by pull-down assay) in the heart, but not the cerebral arteries, are markedly elevated after treatment. In addition, despite constant ERK1/2 abundance, phosphorylated ERK (pERK) activity was elevated at both sites with prominent effect on heart following stimulation. Opposing to the PKA and PKC, as upstream contributors in the pathway, which seem to be similarly affected at both sites following ISO-stimulation, the results imply that the downstream candidates ras and raf, as well as immediate-early genes, have different responses at both sites post-stimulation. The results provide an evidence of site-dependent differential response of ras/raf/ERK pathway after cardiac hypertrophy-induced by ISO-stimulation. This varied response may account for underlying mechanisms of development of cardiac hypertrophy and cerebrovascular events in heart and cerebral arteries, respectively.     

Management of airway complications of burns in children.

Children who have been exposed to smoke in a confined space or who have soot or burns, however minimal, on the face should be admitted to hospital. Respiratory distress may be delayed, but if it is progressive the patient should be curarised, intubated, and mechanically ventilated. Unless ventilation continues for 48 hours, followed by 24 hours'' spontaneous respiration against a positive airway pressure, stridor and pulmonary oedema may recur. An endotracheal tube small enough to allow a leak between it and the oedematous mucosa must be passed to prevent laryngeal damage and subsequent subglottic stenosis. High humidity of inspired gases keeps secretions fluid and the endotracheal tube patent. A high oxygen concentration compensates for deficient oxygen uptake and transport caused by pulmonary lesions and the presence of poisonous compounds interfering with oxygen transport. Dexamethasone to minimise cerebral oedema and antibiotics to reduce the incidence of chest infections should be given.     

The automatic external cardioverter-defibrillator

In-hospital cardiac arrest remains a major problem but new technologies allowing fully automatic external defibrillation are available. These technologies allow the concept of "external therapeutic monitoring" of lethal arrhythmias. Since early defibrillation improves outcome by decreasing morbidity and mortality, the use of this device should improve the outcome of in-hospital cardiac arrest victims. Furthermore, the use of these devices could allow safe monitoring and treatment of patients at risk of cardiac arrest who not necessarily must be in conventional monitoring units (Intensive or Coronary Care Units) saving costs with a more meaningful use of resources. The capability to provide early defibrillation within any patient-care areas should be considered as an obligation ("standard of care") of the modern hospital.