Reading...
Play button
Play button
Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
46 Cards in this Set
- Front
- Back
|
What is needs to be reviewed before a patient goes in to surgery (pre-op assessment)?
|
Hemodynamic Stablity (ECG, BP, HR, Sats)
CXR Airway assessment Afebrile FBC (Hemoglobin) EUC (Renal function) LFT's Clotting/platelet function Skeletal Mallformations |
|
|
What are some important factors that contribute to complication development post-operatively?
|
Co-morbidities
Medications Error in diagnosis, technique, treatment Delay in diagnosis Failure to act on results of monitoring/tests Wrong patient/operation site/operation Lack of knowledge |
|
|
What percentage of body weight corresponds to water composition?
|
60% in men
55% in women 50 % in the elderly |
|
|
What are the advantages of local/regional anaesthesia?
|
The patient can remain concious (airway protection)
Cardiovascular complication reduced Patient requires less nursing care post-operatively Pain is easier to control |
|
|
How does a diathermy work?
|
It is a surgical instrument that applies heat to living tissue through radiofrequency current. The resistance of the tissue causes this energy to be released as heat. It is very useful in surgery as the heat can cut and stop bleeding of small vessels
|
|
|
What is another name for removal of devitalised tissue?
|
Debridement
|
|
|
What are some local and systemic factors that effect wound healing?
|
Local - infection, impaired blood supply, radiotherapy complications, foreign body reactions
Systemic - PVD, malnutriation (proteins, vitamins A+C), Chemotherapy, DM, Rheumatoid arthritis, Jaundice, Uraemia, Marfans, Immunosuppressant drugs, Anticoagulants, Ageing, Obesity, Systemic shock |
|
|
What are the phases of wound healing?
|
Early phase inflammation (neutrophils)
Late phase inflammation (macrophages) Repair phase (granulation tissue) Scar formation + contraction |
|
|
What does granulation tissue formation involve?
|
Fibroblast migration and laying down of extracellula matrix (elastin, collagen, fibronectin)
Angiogenesis (stimulus being hypoxia) |
|
|
What is contraction? What causes it?
|
Contraction is the inward movement of the edges of the injured tissue. It is due to firbroblasts applying tension to the surrounding tissue matrix (occurs 8-10 days post injury)
|
|
|
How do steroids prolong wound healing?
|
Treatment causes prolonged monocytopenia, preventing macrophage migration into the wound
|
|
|
How does irradiation prolong wound healing?
|
Irradiation decreases dermal fibroblasts and decreasing the proliferative potential of endothelium (local irradiation) or depression of bone marrow derived elements (total body irradiation)
|
|
|
How does cytotoxic treatment cause decreased wound healing?
|
Decreased circulating white cells and impairs granulation tissue formation
|
|
|
How does Diabetes prolong impair wound healing?
|
Patients lose the ability to synthesise normal tissue matrix proteins
Microcirculation is also impaired |
|
|
How do anaesthesic drugs depress respiratory function?
|
The bodies sensitivity to hypoxia and hypercapnoea is severely reduced.
|
|
|
How does anaesthetic drugs cause change in lung volume?
|
They act as muscle relaxants so depresses respiratory muscle function
|
|
|
What is the normal V/Q ratio?
|
0.8
|
|
|
What factors effect Total lung capacity?
|
Age
Sex Race Co-morbidities Drugs Musculoskeletal abnormailities |
|
|
How is the risk of pulmonary infection increased by surgery?
|
Anaesthetic gases tend to be dry and damage respiratory epithelium. Endotracheal tubes increase this because they bypass the nasopharynx. Anaesthetic drugs can depress the cough reflex and mucous clearance
Post operatively patients are bed bound |
|
|
What are the main goals of preoperative pharmacologic therapy for patients with pulmonary disease?
|
Fluidification of bronchial secretions
Resolution of bronchial spasms |
|
|
What are the key factors mediating the response to injury?
|
Acute infammatory response
Sympathetic NS Endocrine system |
|
|
What are some clinical manifestations of the bodies response to injury?
|
Tachycardia, Fever, Tachypnoea, Presence of wound/inflammation, Anorexia
|
|
|
What are some laboratory changes in a patient undergoing a response to injury?
|
Leucocytosis, Leucopenia, Hyperglycaemia, Elevated CRP, Altered Acute Phase reactants, Hepatic/renal dysfunction
|
|
|
What are some metabolic manifestations of the response to injury?
|
Hypermetabolic state
- Accelerated Gluconeogenesis - Enhanced Protein Breakdown - Increased Fat Oxidation |
|
|
What are some physiological manifesations of the response to injury?
|
Increased CO
Increased Ventilation Increased membrane transport Weight loss (if prolonged) Wound Healing |
|
|
What causes an increased metabolic rate in the response to injury? what can be done to prevent this?
|
Catecholamines (thyroxine remains normal), alpha and beta-blockage can prevent the hypermetabolic state
|
|
|
Which 4 cytokines commonly induce fevers?
|
IL-1
IL-6 TNF Interferon |
|
|
What are the 3 main obligate glucose consuming tissues?
|
Brain tissue
RBC's Renal Medulla |
|
|
What are 2 reasons to monitor BSL's in patients who had just undergone an operation?
|
Due to the response to injury, patients can be in a hyperglycaemic state can induce insulin-insensitivity. Increased BSL's have also been linked with higher infection rates
|
|
|
In a patient who had just undergone surgery, what happens as a glucose infusion rate increases? In general, what should the maximum glucose infusion rate be?
|
At low levels, glucose is oxidised. As the glucose infusion increases, much of the exogenous glucose is stored in adipose tissue
Glucose infusions should not exceed 4mg/kg/min or alternatively 400g of glucose/day |
|
|
What is the cause of deposition of fat in the post-surgical patient?
|
This occurs as 70% of oxidised fatty-acids re-esterified in the Iiver. This is primarily due to insulin-insensitivity and sympathetic drive
|
|
|
What are the two by-products of fat oxidisation? What is the generic term?
|
Beta-hydroxybutyrate
Acetoacetate Ketone Bodies |
|
|
What are important considerations of protein catabolism in the post-operative surgical patient? Why is it especially important in older patients?
|
1.5kg of protein is lost in the first 3 wks, regardless of nutritional therapy. Most of this loss occurs in skeletal muscle which eventually may manifest as decreased respiratory muscle function, decreased strength and actvity and prolonged hospital stay. Older patients have less protein reserves.
|
|
|
Ketone bodies can be utilised as a feul source by which organs?
|
Brain
Muscle Kidney |
|
|
What are some causes of increased blood flow to certain areas in the post-operative patient?
|
Increased Oxygen Demand
Inflammatory mediators at site of injury Thermoregulatory demands |
|
|
When do complication rates of weight loss post-operatively suddenly rise?
|
When weight loss is greater than 15 percent of the orginal weight
|
|
|
What are 5 forms of shock
|
Hypovolaemic
Cardiogenic Septic Anaphylatic Neurogenic |
|
|
What are some aspects of the history a patient with malnutrition may present with?
|
History of
- Weight loss - Anorexia - Disease processes effecting oral intake/malabsorbtion |
|
|
What is DIC? What are some causes?
|
Explosive activation of the coagulation system, results in over lysis of clots leading to over expenditure of fibrinogen causing bleeding tendency
Malignancy, sepsis, shock, Retained dead fetus, Eclampsia, Intravascular hemolysis |
|
|
How long can a person tolerate fasting without deleterious consequences?
|
Toleration of fasting decreases with age (generally under 60 = 2 wks, 60-80 = 1 wk, 80+ = 5 days)
Toleration decreases with co-morbidities |
|
|
What is the difference between enteral and parenteral routes?
|
Enteral (prefered as it doesnt by pass portal system) is usually given to the stomach or small intestine (small intestine safer due to gastric feeding aspiration risks)
Parenteral is given IV |
|
|
What are some complications of feeding through a tube?
|
Diarrhea
Catheter complications (perforation) Aspiration Intolerance Metabolic complications (hyperglycemia, hyperosmotic non-ketotic coma) |
|
|
What is the sequence for administering pain relief medications if the stimulus is constant?
|
1. Non-opiod medications (paracetamol, non-steroidals)
2. Addition of Opiod therapy (+/- Non-opiods) Q4H 3. Titrate dose up if pain is felt before next dose (20-30% increments) (Typically 5/7.5/10/15/30/45/60/90mg of morphine) 4. Re-evaluate within 24hours 5. Once dose is stable, convert to slow release prep BD 6. Provide short acting prep for breakthrough pain (2 hourly so give 1/6th of total daily dose |
|
|
When is S/C morphine given? How much S/C morphine is equivalent to 30mg oral SR morphine?
|
When oral route not considered most effective (nausea, vomiting, dysphagia, malabsorption)
15mg S/C SR morphine, Sub-cutaneous morphine is 2x as potent as oral morphine |
|
|
What is the normal feeding cycle?
|
Normal progression
1. Well fed state (high insulin) 2. Early Fasting state (high glucagon) 3. Refed state (fat absorbed normally, glucose left to enter peripheral tissues) |
|
|
What are the metabolic changes that occurs progressively in a starving patient?
|
1. Mobilisation of triacylglycerol
2. Several weeks in, ketone bodies are the major source of feul for the heart and brain (decreased need for protein break down) 3. In the end stages, protein degradation accelerates (only store left) leading to multiorgan failure and death |
