Endocrine and Metabolic Response to Surgery Flashcards
name given to the hormonal and metabolic changes which follow injury or trauma
stress response
The overall metabolic effect of the hormonal changes due to surgery, trauma, ect
increased catabolism to provide energy sources and retain salt and water to maintain fluid volume and CV homeostasis
Hypothalamic activation of the sympathetic ANS results in secretion of what to cause tachycardia and hypertension
catecholamines and norepi
Surgery is one of the most potent activators of ACTH and cortisol. How soon can increased plasma concentrations of both hormones be measured during surgery?
within minutes of the first incision
inhibits glucose uptake and use by cells, which spares glucose for use by neurons in situations of glucose scarcity. stimulates protein synthesis and inhibits protein breakdown
growth hormone
increased as part of the stress reponse to surgery and also during exercise. It has little metabolic activity
prolactin
can be modified by anesthetic intervention
cortisol response
Effect of cortisol on carbs, fats, proteins
promotes protein breakdown, gluconeogenesis in liver, and lipolysis increases gluconeogenic precursors
Anti-inflammatory activity of cortisol
inhibit accumulation of macrophages and neutrophils interfering w/prostaglandins
Anabolic hormone. Promotes uptake of glucose into muscle/adipose tissue and stimulates formation of glycogen in liver. Inhibits protein catabolism and lipolysis
insulin
decrease after the induction of anaesthesia, and during surgery there is a failure of this hormone to match catabolic response
insulin
what causes of insulin inhibition during surgery
alpha adrenergic inhibition of β cell secretion
failure of the usual cellular response to insulin which occurs during perioperative period
insulin resistance
This hormone promotes hepatic glycogenolysis, increases gluconeogenesis from amino acids in the liver and has lipolytic activity. However, it’s not a major contributor to hyperglycemic response
glucagon
stimulate the oxygen consumption of most of the metabolically active tissues of the body. increase metabolic rate and heat production
thyroid hormones
What happens to thyroid hormones after surgery?
decrease
Responsible for the hyperglycemia associated with surgery
Cortisol and catecholamines facilitate glucose production, while peripheral use of glucose is decreased
related to the intensity of the surgical injury; the changes follow closely the increases in catecholamines. changes are less marked with minor surgery
blood glucose concentrations
risks of prolonged perioperative hyperglycaemia
wound infection and impaired wound healing
stimulated by increased cortisol concentrations. results in marked weight loss and muscle wasting in patients after major surgical and traumatic injury
protein catabolism
Associated with a faster recovery of immunological parameters, fewer infectious complications and a shorter hospital stay
enteral nutrition
promotes water retention and the production of concentrated urine by direct action on the kidney. may continue for 3-5 days post-op
ADH
secreted from the juxtaglomerular cells of the kidney, partly as a result of increased sympathetic efferent activation
renin
stimulates the release of aldosterone from the adrenal cortex, which in turn leads to Na+ and water reabsorption from the DCT
angiotensin II
activated by afferent neuronal impulses from the site of injury
endocrine response to surgery
Produced from activated leukocytes, fibroblasts, and endothelial cells as an early response to tissue injury and have a major role in mediating immunity and inflammation
cytokines
main cytokine responsible for inducing the systemic changes known as the acute phase response
IL-6
How soon after the start of surgery does the concentration of IL-6 increase?
30-60 minutes
acute phase proteins that act as inflammatory mediators, anti‐proteinases and scavengers and in tissue repair
CRP and fibrinogen
proteins that decrease during the acute phase response
albumin and transferrin
Concentrations of what cations decrease partly as a consequence of the changes in the production of the transport proteins
zinc and iron
inhibit cytokine production
glucocorticoids
inhibits the stress response to surgery, but has no significant effect on cytokine production
regional anesthesia
suppress hypothalamic and pituitary hormone secretion, but want to avoid high doses which require prolonged ventilatory support due to respiratory depression
opioids
will prevent the endocrine and metabolic responses to surgery, reduce incidence of thromboemoblic complications, and decrease paralytic ileus following abdominal procedures
regional/epidural analgesia
associated with rapid recovery and early discharge from hospital due to reduced tissue injury
laparoscopic surgery
patient has edema-indicating that there’s enough fluid in his body-but his vital signs and urine output suggest that he’s hypovolemic. what’s going on?
third spacing, trapping of fluid in interstitial spaces due to decreased oncotic pressure or damage to the capillary membranes
