The Kirby’s Rule of 20 is a classic checklist of 20 important patient parameters. Its creator, Rebecca Kirby, double board-certified in internal medicine and critical care, is the former owner of Animal Emergency Center in Glendale, Wis.
The order and the frequency of each item below are patient-dependent, but all parameters should ideally be evaluated, especially in a critically ill patient.
1. Fluid balance
Both appropriate replacement and maintenance fluids are critical as they are common causes of patient de-compensation and death. Blood pressure and temperature should be monitored when patients are receiving IV fluid therapy.
2. Oncotic pull
Oncotic pull is restored and maintained with crystalloids and colloids during resuscitation and maintenance fluid therapy. They restore and maintain oncotic pull and IV fluid volume while minimizing interstitial fluid accumulation. Albumin should be monitored while patients receive IV fluid therapy.
Ideally maintained between 100 and 200 mg/dl, glucose cannot be considered a good source of calories. Transient hyperglycemia is often a stress response in feline patients but should be rechecked to rule out diabetes mellitus. Hypotensive patients must be monitored closely for hypoglycemia.
Important electrolytes include calcium, sodium, chloride, potassium and magnesium. The acid-base balance also should be monitored. Low potassium is common in critical patients and often requires supplementing maintenance IV fluids. Hypercalemia—often noted in patients such as cats suffering from urinary obstruction—can be corrected via regular insulin or calcium gluconate. Hypophosphatemia is often seen in anorexic patients. Hypernatremia is a sign of a free water deficit and is often associated with improper fluid therapy or renal disease, for example.
Phil Zeltzman, DVM, DACVS, CVJ
Mean arterial pressure should be maintained above 60 mm Hg.
5. Oxygenation and Ventilation
Arterial blood gases should be followed in critical patients to detect hypoxemia, hypercarbia or hyperventilation. This, in turn, can help with the diagnosis of early pulmonary edema or acute respiratory distress syndrome.
6. Level of Consciousness and Mentation
When a change occurs in consciousness or mentation, immediate investigation is warranted to rule out hypotension, hypoglycemia and hyperammonemia. Treatment should be promptly instituted to fight the underlying cause.
7. Blood Pressure
Mean arterial pressure should be maintained above 60 mm Hg. Poor perfusion that is nonresponsive to appropriate IV volume resuscitation should prompt a search for ongoing fluid loss or other causes.
8. Heart Function
Heart rate, rhythm and contractility should be monitored by careful auscultation to detect heart murmurs and gallop rhythms that suggest underlying cardiac disease. Cardiomyopathy and mitral sufficiency can interfere with cardiovascular function, even when it is not the presenting problem.
Albumin concentration should be maintained above 2 g/dl in acutely ill patients. Serum albumin is necessary to maintain adequate oncotic pressure. Mortality is higher in patients with persistent hypoalbuminemia. Albumin can be replenished by giving albumin, fresh frozen plasma or whole blood transfusions.
Monitoring clotting function (ACT, PT and PTT) is important to detect DIC, microthrombi and multiple organ dysfunction early on.
The PCV should be maintained above 20 percent and ideally between 30 and 45 percent. When red blood cells and hemoglobin are deficient, a whole blood or packed red cell transfusion may be indicated if the clinical signs warrant it. On the opposite, if PCV climbs over 55 percent, IV fluids are administered to achieve hemodilution.
12. Renal Function
Shock, severe dehydration, hypotension, hypoxia and nephrotoxic drugs can each contribute to renal dysfunction. Creatinine, BUN and urinalysis should be obtained before fluid resuscitation. Those values should then be monitored closely.
13. Immune Status
The ability of the patient’s body to fight infection is assessed via white blood cell count and differential, fever response and globulin concentration. Appropriate monitoring, reasoned antibiotic use and aseptic technique should be used in immunocompromised patients.
GI motility and mucosal integrity should be determined at least three times a day via auscultation for bowel sounds. Antiemetics and prokinetics can be used as needed.
Drug dosages and the altered metabolism of patients (e.g. with hepatic or renal disease) should be taken into consideration to be sure the patient is medicated appropriately. Proper doses, routes and dosing intervals should be reevaluated daily.
Nutrition is often an overlooked component of patient care, especially in emergency and critical care medicine. The nutritional requirements of the critically ill animal should be addressed as early as possible to minimize tissue catabolism and the development of hepatic lipidosis. When the oral route is not possible, IV and parenteral routes are considered.
Restlessness, tachycardia, depression or irritability may be signs of pain. Appropriate analgesics should be used to maintain patient comfort and cardiovascular function.
18. Nursing Care and Patient Mobilization
“The veterinarian is only as good as the nursing staff,” Kirby wrote. The nursing staff’s level of training should be proportional to the intensity of care required. Patients should be removed from their runs and cages at least twice daily to be evaluated. Any change should be reported to the treating veterinarian.
Urine scalding and fecal soiling should be prevented. Recumbent patients must be turned every four hours to maintain muscle tone and blood flow to the limbs.
IV catheter sites should be checked at least daily to ensure they are patent and not causing swelling or discomfort. Edema in the distal limb should prompt retaping of the catheter to loosen it. Elizabethan collars may be used to protect the catheter and to help in handling aggressive animals.
19. Wound Care
Open wounds and incisions should be evaluated regularly to ensure healing. Bandages and splints should be changed if they become loose, wet or soiled.
Tender loving care should always be provided, as mental health is an integral part of patient care. Owner visits and hand-feeding by the owner should be encouraged when they benefit the pet. Fresh, clean and comfortable bedding always should be available. In a 24-hour environment, the lights are ideally dimmed to maintain biorhythms and sleep patterns.
Incorporating all 20 parameters on your standard treatment sheet may be difficult, but they can easily be added to a separate document. This is how you can progress from offering so-so treatments to providing stellar patient care.
Dr. Phil Zeltzman is a board-certified veterinary surgeon and an author. You may visit his website at www.DrPhilZeltzman.com and follow him at www.facebook.com/DrZeltzman. Columnists’ opinions do not necessarily reflect those of Veterinary Practice News.
Nikki Schneck, a veterinary technician near Pottsville, Pa., contributed to this article.
Originally published in the December 2016 issue of Veterinary Practice News. Did you enjoy this article? Then subscribe today!