multiple organ dysfunction syndrome


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Related to multiple organ dysfunction syndrome: SIRS

multiple

 [mul´tĭ-p'l]
manifold; occurring in various parts of the body at once.
multiple myeloma a malignant neoplasm of plasma cells in which the plasma cells proliferate and invade the bone marrow, causing destruction of the bone and resulting in pathologic fracture and bone pain. It is the most common type of monoclonal gammopathy, characterized by presence of a monoclonal immunoglobulin (immunoglobulin recognized as a single protein), Bence Jones proteins in the urine, anemia, and lowered resistance to infection. Called also plasma cell myeloma.

Diagnostic procedures to confirm suspected multiple myeloma include blood analyses, quantitative immunologic assays of serum and urine, urinalysis, bone marrow aspiration and biopsy, and skeletal x-rays. Findings indicative of the disease are an increased number of plasma cells in the bone marrow (usually over 10 per cent of the total), anemia, hypercalcemia due to release of calcium from deteriorating bone tissue, and elevated blood urea nitrogen, Bence Jones protein in the urine, and osteolytic lesions that give the bone a honeycomb appearance on x-ray and lead to vertebral collapse.
Treatment. Treatment of multiple myeloma involves chemotherapy and radiation to relieve pain and manage the acute lesions of the spinal column. High-dose chemotherapy followed by blood cell rescue has shown some efficacy in certain situations. Individuals diagnosed with multiple myeloma who show no symptoms do not usually receive treatment.
Patient Care. Major problems presented by the patient with multiple myeloma are related to anemia, hypercalcemia, bone pain and pathologic fractures, and emotional distress created by trying to cope with the day-to-day physiologic and emotional aspects associated with the diagnosis of a malignant disease. The more common complications to be avoided are infection, renal failure, and the sequelae of spinal cord compression.

Transfusions with packed red blood cells can help alleviate and minimize some of the more severe symptoms of anemia. It is important that the patient be adequately hydrated to improve viscosity of the blood and circulation, to help avoid hypercalcemia, and to maintain kidney function for excretion of the products of protein metabolism. Continued ambulation and moderate exercise help slow down the loss of minerals, especially calcium, from the bones. Other problems are related to the administration of highly toxic antineoplastic drugs.
Multiple myeloma. Radiographs of the skull, ribs, and vertebrae show multiple punched out lesions. There is anemia secondary to bone marrow lesions that replace red blood cell precursors. Kidney failure is the most common cause of death. The urine contains Bence Jones protein. From Damjanov, 2000.
multiple organ dysfunction syndrome (multiple organ failure) failure of two or more organ systems in a critically ill patient because of a complex and interrelated series of events.
The pathogenesis of multiple organ failure. From Datex Medical Instrumentation, Inc., Tewksbury, MA.
multiple personality disorder dissociative identity disorder.
multiple-puncture test an intracutaneous test in which the material used (such as tuberculin) is introduced into the skin by pressure of several needles or pointed tines or prongs. This procedure is used in mass screenings, but it is not as accurate as other tests because of lack of precise measurement of the amount of medication actually entering the skin.
multiple sclerosis (MS) a chronic neurologic disease in which there are patches of demyelination scattered throughout the white matter of the central nervous system, sometimes extending into the gray matter. The disease primarily affects the myelin and not the nerve cells themselves; any damage to the neurons is secondary to destruction of the myelin covering the axon. The symptoms caused by these lesions are typically weakness, incoordination, paresthesias, speech disturbances, and visual disturbances, particularly diplopia. More specific signs and symptoms depend on the location of the lesions and the severity and destructiveness of the inflammatory and sclerotic processes.

The course of the disease is usually prolonged, with remissions and relapses over many years. Brief exacerbations, even with acute and severe symptoms, are thought to be the result of a transient inflammatory depression of neural transmission. Recovery occurs when there has been no permanent damage to the myelin sheath during the attack. Repeated attacks can, however, eventually permanently denude the axons and leave the yellow sclerotic plaques that are characteristic of the disease. Once the disease process reaches the stage of sclerosis the affected axons cannot recover and there is permanent damage.

The prevalence of MS is not certain because the disease is not one that is reported, and mild cases can be either misdiagnosed or never brought to the attention of a health care provider. It is far more common in the temperate zones of the world than in tropical and subtropical climates. The onset of symptoms most often occurs between the ages of 20 and 40 years, and the disease affects both sexes about equally.

The cause of multiple sclerosis is unknown. It is likely that an inherited immune response is somehow responsible for the production of autoantibodies that attack the myelin sheath. Some authorities believe that infection by one of the slow viruses occurs during childhood and after some years of latency the virus triggers an autoimmune response. Others believe there is an antigen or environmental trigger for the disease.

The diagnosis of multiple sclerosis is difficult because of the wide variety of possible clinical manifestations and the resemblance they bear to other neurological disorders. There is no definitive diagnostic test for the condition, but persons with objectively measured abnormalities of the central nervous system, a history of exacerbation and remission of symptoms, and demonstrable delayed blink reflex and evoked visual response are diagnosed as having either possible or probable multiple sclerosis. With time and progressive worsening of symptoms the diagnosis can become definite.
Treatment. A multidisciplinary approach is required to diagnose the condition and help patients and their families cope with the attendant problems. Multiple sclerosis has an impact on physical activity and life style, role, and interpersonal relationships; therefore, vocational guidance, counseling, and group therapy are helpful. It is important that the patient with severe disability maintain a positive attitude, focusing on functional abilities rather than disabilities. Regeneration of the damaged neural tissue is not possible but retraining and adaptation are. Stress due to trauma, infection, overexertion, surgery, or emotional upset can aggravate the condition and precipitate a flare-up of symptoms.

Supportive measures include a regimen of rest and exercise, a well-balanced diet, avoidance of extremes of heat and cold, avoidance of known sources of infection, and adaptation of a life style that is relatively unstressful while still being as productive as possible.

Therapeutic measures include medications to diminish muscle spasticity; measures to overcome urinary retention (such as credé's method or intermittent catheterization); speech therapy; and physical therapy to maintain muscle tone and avoid orthopedic deformities. Management of MS has been greatly enhanced by the availability of interferons beta-1a and beta-1b. Research support is strong that these medications reduce the frequency and severity of relapses.

Many multiple sclerosis patients and their families receive valuable support and encouragement from communication with others coping with the condition. A local chapter of the National Multiple Sclerosis Society is within reach of most persons in the United States. Information and assistance in all phases of the disease are available by writing to The National Multiple Sclerosis Society, 733 Third Ave., 6th floor, New York, NY 10017, or consulting their web site at http://www.nmss.org.

multiple organ dysfunction syndrome

,

MODS

Progressive failure of two or more organ systems, resulting from acute, severe illnesses or injuries (sepsis, systemic inflammatory response, trauma, burns) and mediated by the body's inability to sufficiently activate its defense mechanisms. Synonym: multiple systems organ failure; multisystem organ failure

Patient care

Patients at risk should be closely monitored to help prevent MODS by prompt recognition and correction of perfusion problems, infection, and organ dysfunction. Patients with MODS often have pulmonary, cardiovascular, renal, and hepatic failure, often followed or accompanied by gram-negative sepsis and disseminated intravascular coagulation. Appropriate medical interventions are initiated for each failing system's problems. Nursing responsibilities include assessing for hemodynamic, acid-base and fluid and electrolyte balance, monitoring and assessing diagnostic study results, coordinating and carrying out prescribed therapies and evaluating patient responses while simultaneously assessing for adverse effects, protecting the patient from nosocomial infections and environmental stressors, and providing emotional support for the patient and family through this type of devastating illness, which has a 90% mortality rate.

The respiratory therapist assists the physician in determining when to intubate the patient and initiate mechanical ventilation. Mechanical ventilation ensures adequate oxygenation and carbon dioxide retention, protects the patient against aspiration, and serves to rest the muscles of breathing and reduce oxygen consumption. The health care provider frequently measures arterial blood gases and pulse oximetry, continually monitors cardiac rhythms, assesses electrolyte and renal function, ensures patient and family comfort and understanding, and protects the patient against complications, including deep venous thrombosis, pressure ulcers, malnutrition, and hospital-acquired infections.

Multiple Organ Dysfunction Syndrome

DRG Category:205
Mean LOS:5.3 days
Description:MEDICAL: Other Respiratory System Diagnoses With Major CC (If the patient develops this syndrome during the hospital stay, the reason for admission will determine the DRG assigned)

Multiple organ dysfunction syndrome (MODS) occurs when altered organ function in an acutely ill patient is present to the extent that homeostasis can no longer be maintained without intervention. MODS was formerly known as multiple system organ failure. The usual sequence of MODS depends somewhat on its cause but often begins with pulmonary failure 2 to 3 days after surgery, followed, in order, by hepatic failure, stress-induced gastrointestinal (GI) bleeding, and renal failure. Mortality rates are linearly related to the number of failed organ systems. Patients with two or more organ systems involved have a mortality rate of approximately 75%, and patients with four organ systems involved have a 100% mortality rate.

MODS was first associated with traumatic injuries in the late 1960s and has subsequently been associated with infection and decreased perfusion to any part of the body. The term multiple organ dysfunction syndrome was adopted in 1991 at a consensus conference of the Society of Critical Care Medicine and the American College of Chest Physicians as it best describes the organ dysfunction that precedes complete failure. Primary MODS, the result of a direct injury or insult to the organ itself, is initiated by a specific precipitating event, such as a pulmonary contusion. The injury or insult causes an inflammatory response within that organ system, and dysfunction develops.

Secondary MODS develops as the result of a systemic response to infection or inflammation. Systemic inflammatory response syndrome (SIRS) is an overwhelming response of the normal inflammatory system, producing systemic effects instead of the localized response normally seen. The inflammatory response is produced by the activation of a series of mediators and results in alterations in blood (selective vasodilation and vasoconstriction), an increase in vascular permeability, white blood cell (WBC) activation, and activation of the coagulation cascade. Mortality rates are high with MODS, and the more organ systems that fail, the higher the mortality. For example, mortality with two-organ failure is 45% to 55%, higher than 80% with three-organ failure, and approaches 100% if the failure of three or more organs persists longer than several days.

Causes

The inflammatory response can be triggered by any event, but it is most often associated with a bacterial infection. The events most often associated with the development of SIRS and MODS are shock, trauma, burns, aspiration, venomous snakebites, cardiac arrest, thromboemboli, myocardial infarction, operative procedures, vascular injury, infection, pancreatitis, and disseminated intravascular coagulation.

Genetic considerations

Heritable defects in the production of cytokines such as interleukin-6 have been suggested in the etiology of MODS. Animal studies have identified an inherited form of complement deficiency, but clear genetic contributions to MODS have not been elucidated.

Gender, ethnic/racial, and life span considerations

Young adults, males twice as often as females, are at particular risk for MODS because they are the primary trauma population. Increased risk in the trauma patient is related to more prolonged hypotension, extensive amounts of tissue damage, and higher infection and sepsis rates. Patients over age 65 who experience MODS have higher rates of mortality. The normal aging process causes dysfunction of organ systems and, in some patients, immunosuppression. With a significant injury or insult, therefore, it is much easier for organ systems in the elderly to fail. Teenagers, young adults, and adults of all ages who abuse alcohol and who are malnourished are also at risk because of the role of alcohol in immunosuppression. There are no known racial or ethnic considerations with MODS.

Global health considerations

Although no data are available on global prevalence, according to the World Health Organization, motor vehicle injury is the ninth leading cause of death in the world, leading to 1.3 million deaths in 2011. Traffic injury is an important cause of sepsis and MODS.

Assessment

History

The patient with MODS has a history of infection, tissue injury, or a perfusion deficit to an organ or body part. Often, this injury or insult is not life-threatening but exposes the person to bacterial contamination. Question the patient (or, if the patient is too ill, the family) to identify the events in the initial insult and any history of preexisting organ dysfunction, such as chronic lung disease, congestive heart failure, and diabetes mellitus. Elicit a complete medication history and the patient’s compliance with medications and ask if the patient has experienced recent weight loss. Determine the patient’s dietary patterns to assess the patient’s nutritional status. Take a history of the patient’s use of cigarettes, alcohol, and other drugs of abuse.

Physical examination

The physical examination of the patient with MODS varies depending on the organ systems involved and the severity of their dysfunction (Table 1). Symptoms vary widely but may include fever, chills, fatigue, muscle weakness, shortness of breath, and mental status changes. The patient will likely appear acutely ill. Expect the patient to develop signs of pulmonary failure first and then hepatic failure and GI bleeding. Renal failure follows. Note that failures of the central nervous system and the cardiovascular system are late signs of MODS.

Organ System Involvement in MODS
Table 1. Organ System Involvement in MODS
ORGAN SYSTEMSYMPTOMS OF DYSFUNCTION
Central nervous systemDecreased level of consciousness, confusion, lethargy
Cardiovascular system
  • Hyperdynamic: tachycardic, normotensive, skin warm and flushed, full bounding pulses
  • Hypodynamic: tachycardic; hypotensive; skin cool and mottled; weak, thready pulses
Pulmonary system
  • Crackles or rales, tachypnea
  • Cyanosis of the nailbeds and mucous membranes, dyspnea
GI systemDiminished or absent bowel sounds, abdominal distention, intolerance of tube feedings, upper or lower gastrointestinal bleeding, diarrhea
Hepatic systemJaundice, petechiae, increased bruising
Renal systemPolyuria, oliguria, or anuria
Coagulation systemOozing or bleeding from intravenous sites or invasive line sites; bruising and petechiae; bleeding into body parts or cavities; cool, pale to mottled extremities; necrotic digits
General appearanceWeight loss and muscle wasting; temperature < 98.8°F or > 104.4°F

Psychosocial

The patient with MODS may be fully conscious, partially conscious, or unconscious. If the patient is oriented, she or he is likely to be very anxious and fatigued and also confused, lethargic, or comatose. Assess the patient’s ability to cope with a prolonged life-threatening illness and the changes in roles that a severe illness brings. The patient may experience fear because of a real threat to her or his life.

Diagnostic highlights

General Comments: Diagnostic data are collected to establish the dysfunction of each of the body’s systems (Table 2).

TestNormal ResultAbnormality With ConditionExplanation
Complete blood countRed blood cells (RBCs): 4–5.5 million/μL; WBCs: 4,500–11,000/μL; hemoglobin (Hgb): 12–18 g/dL; hematocrit (Hct): 37%–54%; reticulocyte count: 0.5%–2.5% of total RBCs; platelets: 150,000–400,000/μLVaries with condition: > 12,000 mm3 or < 4,000 mm3 or > 10% band cells (immature cells); RBCs, Hgb, Hct, blood cells, decreasedUnderlying disorder may cause alterations in blood cell counts; SIRS leads to production of inflammatory mediators and alterations in WBC counts; hematological failure may lead to suppression of cell production
Partial thromboplastin time (activated; APPT)Varies by laboratory; generally 21–35 secProlonged; may be prolonged > 80 secMay be prolonged if liver failure and hematological failure occurs
Prothrombin time (PT)Varies by laboratory; generally 11–13 secProlonged > 15 secMay be prolonged if liver failure occurs

Other Tests: Electrocardiogram, multiple cultures and sensitivities (blood, wound, urine, sputum, catheters), arterial blood gases, pulmonary artery pressure monitoring, cardiac output and index, derived oxygen variables (oxygen delivery, oxygen consumption), electrolytes, glucose

Definitions of Organ Failure
Table 2. Definitions of Organ Failure
ORGANDEFINITION OF FAILUREDIAGNOSTIC FINDINGS
LungsNeed for ventilator-assisted breathing to treat hypoxemia for 5 days in the postoperative period or until death
  • Decreased Pao2 and SaO2
  • Decreased Paco2
  • Increased shunt fraction
  • Decreased vital capacity and functional residual capacity
  • Decreased static compliance
KidneysSerum creatinine concentration > 2 mg/dL; for patients with preexisting renal disease, doubling of admission serum creatinine level
  • Increased serum creatinine
  • Urine specific gravity < 1.012
  • Urine sodium > 40 mEq/L
LiverSerum bilirubin concentration > 2 mg/dL with elevation of either serum aspartate aminotransferase concentration or lactic dehydrogenase concentration above twice normalSee definition
Gastrointestinal tractRequirement of two units of blood replacement within 24 hr for presumed stress bleeding or endoscopic confirmation of upper GI bleeding from acute GI ulcers
  • Dropping Hgb and Hct
  • Visualization of ulcers during surgery or endoscopy

Primary nursing diagnosis

Diagnosis

Risk for infection related to microorganism invasion, immunosuppression, malnutrition, and presence of invasive monitoring devices

Outcomes

Immune status; Knowledge: Infection control; Risk control; Risk detection; Nutrition status; Treatment behavior: Illness or injury; Hydration

Interventions

Infection control; Infection protection; Surveillance; Fluid/electrolyte management; Medication management: Temperature regulation

Planning and implementation

Collaborative

Management of the patient with MODS begins with the recognition of those patients who are at an increased risk for the syndrome. Care must be taken to prevent infection and maintain adequate tissue oxygenation to all body parts. Despite improvement in medical therapies, the mortality rate of MODS remains high.

Treatment of the patient with MODS can be divided into four main areas: anti-infectives, maintenance of tissue perfusion and oxygenation, nutritional support, and immunomodulation. Anti-infective therapy is guided by culture and sensitivity reports. Any potential source of infection should be investigated and eliminated. Antifungal and antiviral agents are used primarily with immunocompromised patients, who are especially susceptible to fungal and viral infections.

Maintaining and monitoring tissue perfusion and oxygenation are crucial to the survival of the patient with MODS. Measurement of oxygen delivery and consumption is necessary to guide fluid replacement therapy and inotropic support of cardiac function. To maximize all components of oxygen delivery (particularly cardiac index, Hgb, and oxygen saturation), the physician maintains the Hct within the normal range or even at a supranormal level with blood transfusions. Mechanical ventilation with positive end expiratory pressure and modes such as pressure-control ventilation and inverse I:E ratio (inspiration:expiration) ventilation are used to maintain adequate oxygenation and oxygen delivery. The success of maintaining oxygen delivery is evaluated by following the trend of oxygen consumption. Metabolic demands dramatically increase in MODS. When oxygen delivery cannot meet the body’s metabolic demands, these demands may be decreased with sedation, pharmacologic paralysis, and temperature control. The goal in the future is to develop medications that allow for immunomodulation therapy to alter the detrimental effects of the systemic immune-inflammatory response. Tumor necrosis factor and interleukin-1 are two cytokines that exert a broad effect on the endothelium, leukocytes, and fibroblasts. Experts hope that modulation of both of these cytokines can decrease many of the body’s responses to inflammation. The presence of endotoxin, a substance that is released with the destruction of gram-negative bacteria, stimulates the inflammatory response. Modulation of endotoxin would also decrease many of the body’s responses to inflammation.

Pharmacologic highlights

Medication or Drug ClassDosageDescriptionRationale
Vasopressor therapyVaries with drugDopamine, epinephrine, norepinephrine, phenylephrine, vasopressinMaintains circulation and tissue perfusion after volume resuscitation has been accomplished
Anti-infective therapy; antifungal agents; antiviral agentsVaries with drugTherapy focuses on dysfunctional system and culture results; cefotaxime, ceftriaxone, cefuroxime, ticarcillin-clavulanate, piperacillin-tazobactam, imipenem-cilastatin, clindamycin, metronidazolePrevents and controls infection
H2 receptor antagonistVaries with drugRanitidine (Zantac), cimetidine (Tagamet), famotidine (Pepcid), nizatidine (Axid)Blocks gastric secretion and maintains the pH of gastric contents above 4

Other Drugs: Recombinant human-activated protein C was withdrawn from the market in 2011 for use in sepsis and MODS; corticosteroids (controversial)

Independent

Any potential source of infection should be eliminated if possible. Change the dressing on all invasive line sites and surgical wounds according to protocol to keep the area free of infection and to monitor for early signs of infection. Maintain aseptic technique with all dressing changes and manipulation of intravenous lines. Institute measures to prevent aspiration when patients are placed on enteral feedings. Keep the head of the bed elevated and check for residual volume and tube placement every 4 hours.

To limit the patient’s oxygen expenditure, provide frequent rest periods and create a quiet environment whenever possible. Schedule procedures and nursing care interventions so that the patient has periods of uninterrupted rest. Manage situations of increased metabolic demand—such as fever, agitation, alcohol withdrawal, and pain—promptly so that the patient conserves energy and limits oxygen consumption.

Monitor the patient’s environment for sensory overload. Provide purposeful, planned stimuli and keep extraneous, constant noises to a minimum. Provide for planned, uninterrupted rest periods to avoid sleep deprivation. Monitor bony prominences and areas of high risk for skin breakdown. Note that MODS is one of the most critical illnesses that a patient can develop. Although the patient might be well sedated and unresponsive, the family or significant others are generally very anxious, upset, and frightened that the patient might not survive.

These fears are realistic, particularly if multiple organs are involved. Provide the significant others with accurate information about the patient’s course and his or her prospects for recovery. Encourage the legal representative to participate in decisions about extraordinary measures to keep the patient alive if the patient cannot speak for himself or herself. Determine if the patient has a living will or has discussed his or her desire to be kept alive by technology during a potentially terminal illness. If the decision is to terminate life support, work with the significant others to provide a dignified death for the patient in an environment that allows the family to participate and grieve appropriately. Provide referrals to the chaplain, clinical nurse specialist, or grief counselor as needed.

Evidence-Based Practice and Health Policy

Kyle, U.G., Coss Bu, J.A., Kennedy, C.E., & Jefferson, L.S. (2010). Organ dysfunction is associated with hyperglycemia in critically ill children. Intensive Care Medicine, 36(2), 312–320.

  • Investigators conducted a retrospective cohort study among 110 patients being treated in a pediatric intensive care unit and found that patients with dysfunction of three or more organs were 6.1 times more likely to experience intermittent hyperglycemia (95% CI, 1.8 to 21.2; p = 0.004), even when being treated with an insulin drip. Fifty-five percent of patients had dysfunction of three or more organs.
  • Severe hyperglycemia was experienced by a significantly greater proportion of patients with dysfunction of three or more organs (17.2%) compared to patients with dysfunction of less than three organs (2.2%) (p = 0.01). However, hyperglycemia had no significant effect on survival, which was 70% overall at hospital discharge.

Documentation guidelines

  • Physical assessment findings:
    • Neurological: Mental status response to stimuli; if pharmacologically paralyzed, then peripheral nerve stimulation testing
    • Pulmonary: Respiratory rate, auscultation findings, amount of ventilatory support, oxygen saturation by pulse oximetry
    • Hemodynamics: Cardiac output/index, right and left ventricular measures of preload and afterload; oxygen delivery; oxygen consumption
    • Renal function: Fluid intake and urine output
    • Hepatic function: Color of skin and sclera, presence of petechiae, bruising, oozing, or frank bleeding
  • Response to acute, life-threatening illness: Anxiety level, coping

Discharge and home healthcare guidelines

Although no specific adaptive structural changes need to be made, assess the patient’s individual needs near the time of discharge. Because organ dysfunction or failure is individualized, home-care preparation should be based on meeting the individual’s needs. Be sure the patient understands all medications prescribed, including dosage, route, action, and side effects.

Describe the importance of avoiding fatigue and of taking frequent rests. Teach the patient to eat small, frequent meals to maintain adequate nutrition. Teach the patient any needed postoperative care: incision care, signs and symptoms of infection, pain management, activity restrictions. Also teach the patient when to report signs and symptoms of infection to the primary healthcare provider.

multiple

manifold; occurring in various parts of the body at once.

multiple alleles
see allele.
multiple birth
more than one offspring in a gestation and parturition.
multiple causation
a disease in which a combination, or alternative combinations, of causes, are required to produce it. Called also multifactorial etiology.
multiple-crush
surgical instruments, e.g. heavy duty emasculators, ecraseurs in which each jaw has more than one crushing surface, mounted one behind the other, each successive surface coming into contact with its counterpart as increasing pressure is applied to the handles of the instrument.
multiple endochondromas
multiple fission
a method of reproduction in protozoa. See schizogony.
multiple infection
simultaneous infection with more than one virus or a combination of virus and bacteria may be caused by one agent lowering resistance to the other. There may be synergism between the agents.
multiple least squares regression
the major method of analysis used to sort through a large number of potential risk factors permitting the examination of one factor while the other factors in the regression equation are held mathematically constant.
multiple limb defects
patients with more than one congenital limb defect.
multiple myeloma
see multiple myeloma.
multiple organ dysfunction syndrome
in critical care medicine, a state in which intervention is required to maintain homeostasis. Called also MODS.
multiple ovulation
an important feature in the technique of embryo transfer. See superovulation.
multiple pregnancies
twins, triplets and more in usually uniparous species.
multiple regression
an analytical method which determines the relationship between a dependent variable and one or more independent variables.
multiple risk
situations in which more than one risk factor for a disease is present and their combined presence contributes to an increased risk.
multiple suckling
when a cow accepts more calves to suckle than her own; a system for foster-rearing of orphan or purchased calves.
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