Podcast
Questions and Answers
What initial symptoms can be caused by LA blockage in the brain?
What initial symptoms can be caused by LA blockage in the brain?
- Confusion and agitation (correct)
- Increased heart rate
- Decreased respiratory rate
- Enhanced social interaction
What is the consequence of LA preventing oxidative phosphorylation?
What is the consequence of LA preventing oxidative phosphorylation?
- Decreased ATP production (correct)
- Increased ATP production
- Increased O2 utilization
- Increased bicarbonate production
What happens to the heart due to ion channel blockages caused by LAs?
What happens to the heart due to ion channel blockages caused by LAs?
- Increase in refractory periods
- Enhanced myocardial contractility
- Normal cardiac function
- Conduction defects (correct)
What is a potential result of LAs leading to anaerobic metabolism?
What is a potential result of LAs leading to anaerobic metabolism?
Which function is primarily affected by the lack of ATP due to LAs?
Which function is primarily affected by the lack of ATP due to LAs?
What critical balance does sodium maintain in relation to calcium during the cardiac cycle?
What critical balance does sodium maintain in relation to calcium during the cardiac cycle?
How does LA affect the calcium levels in cardiac tissues?
How does LA affect the calcium levels in cardiac tissues?
What results from the blockade of sodium channels in relation to potassium and calcium?
What results from the blockade of sodium channels in relation to potassium and calcium?
What is the main organ system affected by local anaesthetic toxicity?
What is the main organ system affected by local anaesthetic toxicity?
Why does the duration of action for bupivacaine present a greater risk of toxicity?
Why does the duration of action for bupivacaine present a greater risk of toxicity?
What is a primary initial treatment for local anaesthetic systemic toxicity (LAST)?
What is a primary initial treatment for local anaesthetic systemic toxicity (LAST)?
What happens to the level of free drug in the systemic circulation after plasma saturation with local anaesthetic?
What happens to the level of free drug in the systemic circulation after plasma saturation with local anaesthetic?
What role does lipid emulsion play in treating LAST?
What role does lipid emulsion play in treating LAST?
What is required for the metabolism of local anaesthetics in the body?
What is required for the metabolism of local anaesthetics in the body?
What major problem arises when mitochondrial function is compromised during local anaesthetic toxicity?
What major problem arises when mitochondrial function is compromised during local anaesthetic toxicity?
What immediate action is necessary to ensure adequate oxygenation in a patient with LAST?
What immediate action is necessary to ensure adequate oxygenation in a patient with LAST?
What happens to cardiac output during prolonged PR interval due to toxic levels of local anaesthetics?
What happens to cardiac output during prolonged PR interval due to toxic levels of local anaesthetics?
How does local anaesthetic affect nerve impulses being sent to the brain?
How does local anaesthetic affect nerve impulses being sent to the brain?
What is one of the direct effects of local anaesthetic toxicity on the cardiac system?
What is one of the direct effects of local anaesthetic toxicity on the cardiac system?
Which of these is a complication of inadequate conduction in the heart due to LAST?
Which of these is a complication of inadequate conduction in the heart due to LAST?
Which of the following best describes a consequence of sodium channel inhibition by local anaesthetics?
Which of the following best describes a consequence of sodium channel inhibition by local anaesthetics?
Which factor does NOT influence the rate of absorption of local anaesthetics into systemic circulation?
Which factor does NOT influence the rate of absorption of local anaesthetics into systemic circulation?
What is indicated if a patient with LAST shows a decline in consciousness level?
What is indicated if a patient with LAST shows a decline in consciousness level?
How does lipid emulsion improve cardiac function in LAST?
How does lipid emulsion improve cardiac function in LAST?
What is the main reason why local anesthetics are given?
What is the main reason why local anesthetics are given?
What is the chemical characteristic of local anesthetics that allows them to cross cell membranes?
What is the chemical characteristic of local anesthetics that allows them to cross cell membranes?
What is the primary mechanism of action for local anesthetics?
What is the primary mechanism of action for local anesthetics?
What is the main reason for local anesthetic systemic toxicity?
What is the main reason for local anesthetic systemic toxicity?
What is the typical timeframe for the development of symptoms after local anesthetic administration?
What is the typical timeframe for the development of symptoms after local anesthetic administration?
Which of the following statements is true regarding local anesthetics and their lipid solubility?
Which of the following statements is true regarding local anesthetics and their lipid solubility?
What is the role of sodium in muscle contraction and nerve transmission?
What is the role of sodium in muscle contraction and nerve transmission?
How does local anesthetic systemic toxicity affect the heart?
How does local anesthetic systemic toxicity affect the heart?
What primary metabolic disturbance is often observed in burn patients due to abnormal glucose production and insulin resistance?
What primary metabolic disturbance is often observed in burn patients due to abnormal glucose production and insulin resistance?
Which of the following best describes the recommendation for blood analysis in burn patients?
Which of the following best describes the recommendation for blood analysis in burn patients?
If a burn patient's consciousness level is declining, what should be a primary concern for healthcare providers?
If a burn patient's consciousness level is declining, what should be a primary concern for healthcare providers?
What percentage of the body's total oxygen consumption does the brain require?
What percentage of the body's total oxygen consumption does the brain require?
During the 'exposure' phase of burn patient assessment, what actions are typically performed?
During the 'exposure' phase of burn patient assessment, what actions are typically performed?
What is the primary goal of burns resuscitation?
What is the primary goal of burns resuscitation?
Which zone of a burn is characterized by increased tissue perfusion?
Which zone of a burn is characterized by increased tissue perfusion?
What can cause a zone of stasis to contribute to a deeper wound?
What can cause a zone of stasis to contribute to a deeper wound?
At what percentage of total body surface area (TBSA) does a burn typically begin to cause a systemic response?
At what percentage of total body surface area (TBSA) does a burn typically begin to cause a systemic response?
What is the effect of burns on capillary permeability?
What is the effect of burns on capillary permeability?
Which of the following is NOT a primary cause of burns?
Which of the following is NOT a primary cause of burns?
Which of the following is a typical systemic cardiovascular response to a significant burn?
Which of the following is a typical systemic cardiovascular response to a significant burn?
What is the result of peripheral and splanchnic vasoconstriction following a significant burn?
What is the result of peripheral and splanchnic vasoconstriction following a significant burn?
Which layer of the skin is primarily responsible for thermoregulation?
Which layer of the skin is primarily responsible for thermoregulation?
What is a possible cause of decreased myocardial contractility, following a significant burn?
What is a possible cause of decreased myocardial contractility, following a significant burn?
What is the primary characteristic of a first-degree burn?
What is the primary characteristic of a first-degree burn?
Which type of burn is characterized by blisters, red skin, and blanching with capillary refill?
Which type of burn is characterized by blisters, red skin, and blanching with capillary refill?
What is a key feature of a third-degree burn?
What is a key feature of a third-degree burn?
Which zone of a burn injury is characterized by tissue damage due to protein coagulation?
Which zone of a burn injury is characterized by tissue damage due to protein coagulation?
What is a main characteristic of the zone of stasis?
What is a main characteristic of the zone of stasis?
Which skin layer is responsible for regenerating the epidermis?
Which skin layer is responsible for regenerating the epidermis?
What is the primary reason for decreased blood flow to organs following severe burns?
What is the primary reason for decreased blood flow to organs following severe burns?
How do inflammatory mediators primarily affect the respiratory system in burn patients?
How do inflammatory mediators primarily affect the respiratory system in burn patients?
What is the typical change in basal metabolic rate following severe burns?
What is the typical change in basal metabolic rate following severe burns?
Why is early and increased feeding necessary for burn patients?
Why is early and increased feeding necessary for burn patients?
What condition develops in burn patients due to increased glucose production and insulin resistance?
What condition develops in burn patients due to increased glucose production and insulin resistance?
Which of the following physiological responses occurs to compensate for reduced stroke volume in burn patients?
Which of the following physiological responses occurs to compensate for reduced stroke volume in burn patients?
What is the first step in managing a burn patient?
What is the first step in managing a burn patient?
What does the absence of blanching during a capillary refill test (CRT) indicate about a burn?
What does the absence of blanching during a capillary refill test (CRT) indicate about a burn?
What is a key indication for considering Rapid Sequence Intubation (RSI) with an endotracheal tube in a burn patient?
What is a key indication for considering Rapid Sequence Intubation (RSI) with an endotracheal tube in a burn patient?
Why might a patient with severe burns around the chest experience dyspnoea?
Why might a patient with severe burns around the chest experience dyspnoea?
Which physiological response does the body initiate to conserve fluid in a patient with severe burns?
Which physiological response does the body initiate to conserve fluid in a patient with severe burns?
What is the primary reason for hypothermia in a patient with a third-degree burn?
What is the primary reason for hypothermia in a patient with a third-degree burn?
The 'lethal triad' in burn patients consists of hypothermia, coagulopathy, and:
The 'lethal triad' in burn patients consists of hypothermia, coagulopathy, and:
What is the primary reason for increased heart rate in burn patients when the blood pressure remains stable?
What is the primary reason for increased heart rate in burn patients when the blood pressure remains stable?
Why is it critical to control the room temperature for a patient with third-degree burns?
Why is it critical to control the room temperature for a patient with third-degree burns?
What is the significance of 'vascular permeability' in the context of burn injuries?
What is the significance of 'vascular permeability' in the context of burn injuries?
Which of the following rhythm disturbances is considered a 'shockable' cardiac rhythm?
Which of the following rhythm disturbances is considered a 'shockable' cardiac rhythm?
Which cardiac rhythm is characterized by the absence of electrical activity and requires interventions other than defibrillation?
Which cardiac rhythm is characterized by the absence of electrical activity and requires interventions other than defibrillation?
What is the initial step according to the content, when confronted with a patient exhibiting a possible Pulseless Ventricular Tachycardia (PVT) rhythm?
What is the initial step according to the content, when confronted with a patient exhibiting a possible Pulseless Ventricular Tachycardia (PVT) rhythm?
Which of the following best describes Pulseless Electrical Activity (PEA)?
Which of the following best describes Pulseless Electrical Activity (PEA)?
If a patient's ECG shows Ventricular Fibrillation (VF), what is the MOST appropriate initial intervention?
If a patient's ECG shows Ventricular Fibrillation (VF), what is the MOST appropriate initial intervention?
If a patient's blood analysis shows a pH of 7.2 with a reduced bicarbonate level but normal CO2, which condition is most likely present?
If a patient's blood analysis shows a pH of 7.2 with a reduced bicarbonate level but normal CO2, which condition is most likely present?
What does a Base Excess (BE) of +3 mmol/L typically indicate about a patient's acid-base balance?
What does a Base Excess (BE) of +3 mmol/L typically indicate about a patient's acid-base balance?
Why is it crucial to obtain an arterial blood sample promptly after drawing it?
Why is it crucial to obtain an arterial blood sample promptly after drawing it?
What is the significance of checking a patient's temperature when interpreting blood gas analysis results?
What is the significance of checking a patient's temperature when interpreting blood gas analysis results?
Elevated levels of which electrolyte would be most concerning in relation to cardiac arrest, as indicated in the text?
Elevated levels of which electrolyte would be most concerning in relation to cardiac arrest, as indicated in the text?
In arterial blood gas analysis, what does the partial pressure of a gas (Pa) directly indicate?
In arterial blood gas analysis, what does the partial pressure of a gas (Pa) directly indicate?
When the kidneys fail to produce enough bicarbonate, what specific condition is likely to occur in the patient?
When the kidneys fail to produce enough bicarbonate, what specific condition is likely to occur in the patient?
A patient has a PaCO2 level of 7.0 kPa and normal bicarbonate levels. What does this likely indicate?
A patient has a PaCO2 level of 7.0 kPa and normal bicarbonate levels. What does this likely indicate?
If a patient is receiving 50% oxygen, what is the expected PaO2 value, assuming no underlying respiratory issue?
If a patient is receiving 50% oxygen, what is the expected PaO2 value, assuming no underlying respiratory issue?
Which of the following best describes the function of bicarbonate (HCO3) in the body?
Which of the following best describes the function of bicarbonate (HCO3) in the body?
What is the primary physiological response of the lungs when attempting to correct acidosis?
What is the primary physiological response of the lungs when attempting to correct acidosis?
What is the normal range for arterial blood pH, indicating a healthy balance?
What is the normal range for arterial blood pH, indicating a healthy balance?
What is the normal range for bicarbonate (HCO3) in arterial blood gas analysis, indicating optimal kidney function?
What is the normal range for bicarbonate (HCO3) in arterial blood gas analysis, indicating optimal kidney function?
What is the primary metabolic disturbance observed in burn patients due to abnormal glucose production and insulin resistance?
What is the primary metabolic disturbance observed in burn patients due to abnormal glucose production and insulin resistance?
Which of the following is a recommended blood analysis for burn patients?
Which of the following is a recommended blood analysis for burn patients?
What primarily causes burns?
What primarily causes burns?
Which layer of the skin is mainly involved in thermoregulation?
Which layer of the skin is mainly involved in thermoregulation?
What characterizes a second-degree superficial burn?
What characterizes a second-degree superficial burn?
What happens to the tissue in the zone of stasis?
What happens to the tissue in the zone of stasis?
Which type of burn is painless due to nerve damage?
Which type of burn is painless due to nerve damage?
What is the primary feature of a first-degree burn?
What is the primary feature of a first-degree burn?
What is the zone of coagulation in burn injuries?
What is the zone of coagulation in burn injuries?
What characterizes a second-degree deep dermal burn?
What characterizes a second-degree deep dermal burn?
What causes goosebumps in response to cold temperatures?
What causes goosebumps in response to cold temperatures?
What is the main aim of burns resuscitation?
What is the main aim of burns resuscitation?
What is the status of tissue in the zone of hyperaemia?
What is the status of tissue in the zone of hyperaemia?
What occurs when the zone of stasis is damaged?
What occurs when the zone of stasis is damaged?
Which systemic response is triggered once a burn reaches 30% of total body surface area?
Which systemic response is triggered once a burn reaches 30% of total body surface area?
What happens to myocardial contractility in response to burn injuries?
What happens to myocardial contractility in response to burn injuries?
What effect does prolonged hypotension have on burn injuries?
What effect does prolonged hypotension have on burn injuries?
What is a consequence of increased capillary permeability following significant burns?
What is a consequence of increased capillary permeability following significant burns?
What is a likely result of vasoconstriction occurring after a significant burn?
What is a likely result of vasoconstriction occurring after a significant burn?
What is one of the impacts of the release of cytokines at the burn site?
What is one of the impacts of the release of cytokines at the burn site?
What can cause a burn wound to deepen and widen?
What can cause a burn wound to deepen and widen?
What is the primary cause of hyperglycemia in burn patients?
What is the primary cause of hyperglycemia in burn patients?
Which metabolic change occurs in burn patients?
Which metabolic change occurs in burn patients?
What physiological change might occur in a burn patient within the first 24-72 hours?
What physiological change might occur in a burn patient within the first 24-72 hours?
Which respiratory issue is commonly associated with severe burns?
Which respiratory issue is commonly associated with severe burns?
What kind of management is crucial if a burn affects the airway areas?
What kind of management is crucial if a burn affects the airway areas?
What hormone primarily contributes to the metabolic effects seen in burn patients?
What hormone primarily contributes to the metabolic effects seen in burn patients?
What typical response may occur in the cardiovascular system following significant burns?
What typical response may occur in the cardiovascular system following significant burns?
What is a significant nutritional consideration for burn patients?
What is a significant nutritional consideration for burn patients?
What effect does reduced blood flow to the splanchnic region have on burn patients?
What effect does reduced blood flow to the splanchnic region have on burn patients?
What type of burn is characterized by pain and blisters, but can blanch with capillary refill?
What type of burn is characterized by pain and blisters, but can blanch with capillary refill?
What is a significant consideration when performing rapid sequence intubation (RSI) in an emergency situation?
What is a significant consideration when performing rapid sequence intubation (RSI) in an emergency situation?
What occurs in patients with severe burns that impacts their ability to breathe effectively?
What occurs in patients with severe burns that impacts their ability to breathe effectively?
What is the result of increased vascular permeability in burn patients?
What is the result of increased vascular permeability in burn patients?
How does hypothermia occur in burn patients?
How does hypothermia occur in burn patients?
What physiological response occurs to maintain blood pressure following a significant burn?
What physiological response occurs to maintain blood pressure following a significant burn?
What is the lethal triad associated with severe burns?
What is the lethal triad associated with severe burns?
How does rapid breathing occur in burn patients experiencing respiratory acidosis?
How does rapid breathing occur in burn patients experiencing respiratory acidosis?
What is a notable clinical sign of third-degree burns?
What is a notable clinical sign of third-degree burns?
What happens to the patient's body temperature in cases of severe burns despite peripheral vasoconstriction?
What happens to the patient's body temperature in cases of severe burns despite peripheral vasoconstriction?
What triggers the urge to breathe in patients with impaired respiratory function?
What triggers the urge to breathe in patients with impaired respiratory function?
Flashcards
Local Anaesthetic Systemic Toxicity
Local Anaesthetic Systemic Toxicity
A life-threatening condition due to local anaesthetic administration.
Symptoms Timing
Symptoms Timing
Symptoms occur typically within 10 minutes, may take up to an hour.
Composition of Local Anaesthetics
Composition of Local Anaesthetics
Made of water-soluble salts of lipid-soluble alkaloids.
Lipophilic
Lipophilic
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Mechanism of Action
Mechanism of Action
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Sodium's Role
Sodium's Role
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Toxicity Risks
Toxicity Risks
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Action Potential Impact
Action Potential Impact
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Toxicity of Local Anaesthetics (LA)
Toxicity of Local Anaesthetics (LA)
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Absorption of LA
Absorption of LA
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Bupivacaine Characteristics
Bupivacaine Characteristics
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Plasma Saturation with LA
Plasma Saturation with LA
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Metabolism Dependence
Metabolism Dependence
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Mitochondrial Dysfunction
Mitochondrial Dysfunction
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CNS Toxicity Effects
CNS Toxicity Effects
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Key Organs Affected by Toxicity
Key Organs Affected by Toxicity
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Local Anesthetics (LAs) effects
Local Anesthetics (LAs) effects
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Symptoms of LA blockage
Symptoms of LA blockage
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Seizures from LA
Seizures from LA
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CNS depression effects
CNS depression effects
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Cardiac Toxicity of LAs
Cardiac Toxicity of LAs
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Oxidative Phosphorylation
Oxidative Phosphorylation
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Effects on cardiac function
Effects on cardiac function
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Ion channel blockade
Ion channel blockade
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Prolonged PR Interval
Prolonged PR Interval
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Hypotension
Hypotension
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Tachycardia
Tachycardia
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Local Anaesthetic Systemic Toxicity (LAST)
Local Anaesthetic Systemic Toxicity (LAST)
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Lipid Rescue Pack
Lipid Rescue Pack
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100% Oxygen (O2)
100% Oxygen (O2)
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Intralipid/Lipid emulsion
Intralipid/Lipid emulsion
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Intravenous (IV) Access
Intravenous (IV) Access
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Fluid Demand in Burns
Fluid Demand in Burns
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Contractility and HR
Contractility and HR
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Respiratory Changes in Burns
Respiratory Changes in Burns
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Metabolic Rate Increase
Metabolic Rate Increase
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Gluconeogenesis
Gluconeogenesis
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Insulin Resistance in Burns
Insulin Resistance in Burns
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Burn Treatment Steps
Burn Treatment Steps
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Hormonal Response to Burns
Hormonal Response to Burns
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Burn
Burn
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Epidermis
Epidermis
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Dermis
Dermis
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1st Degree Burn
1st Degree Burn
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2nd Degree Burn
2nd Degree Burn
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3rd Degree Burn
3rd Degree Burn
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Zone of Coagulation
Zone of Coagulation
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Zone of Stasis
Zone of Stasis
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Burn Resuscitation Aim
Burn Resuscitation Aim
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Zone of Hyperaemia
Zone of Hyperaemia
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Systemic Response of Burns
Systemic Response of Burns
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Capillary Permeability Increase
Capillary Permeability Increase
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Vasoconstriction
Vasoconstriction
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Myocardial Contractility Decrease
Myocardial Contractility Decrease
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Systemic Hypotension
Systemic Hypotension
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Hyperglycaemia
Hyperglycaemia
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Insulin Resistance
Insulin Resistance
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Oxygen Demand in Brain
Oxygen Demand in Brain
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RSI with ET Tubes
RSI with ET Tubes
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Signs of Burns
Signs of Burns
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Respiratory Acidosis
Respiratory Acidosis
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Fluid Loss in Burns
Fluid Loss in Burns
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Temp Regulation in Burns
Temp Regulation in Burns
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Lethal Triad
Lethal Triad
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Importance of IV Access
Importance of IV Access
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Dyspnea from Burns
Dyspnea from Burns
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Shockable Rhythm
Shockable Rhythm
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Ventricular Fibrillation (VF)
Ventricular Fibrillation (VF)
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Pulseless Ventricular Tachycardia (PVT)
Pulseless Ventricular Tachycardia (PVT)
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Non-Shockable Rhythm
Non-Shockable Rhythm
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Asystole
Asystole
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Arterial Blood Gas (ABG)
Arterial Blood Gas (ABG)
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pH Normal Range
pH Normal Range
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PaO2
PaO2
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PaCO2
PaCO2
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HCO3 (Bicarbonate)
HCO3 (Bicarbonate)
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Role of Lungs in pH
Role of Lungs in pH
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Role of Kidneys in pH
Role of Kidneys in pH
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Acidosis Definition
Acidosis Definition
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Base Excess (BE)
Base Excess (BE)
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Respiratory vs Metabolic
Respiratory vs Metabolic
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Sampling Site for ABG
Sampling Site for ABG
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Correcting pH
Correcting pH
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Complications from Electrolytes
Complications from Electrolytes
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Breathing Difficulty in Burns
Breathing Difficulty in Burns
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Temperature Regulation in Burns
Temperature Regulation in Burns
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Signs of Severe Burns
Signs of Severe Burns
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Circulatory Response to Burns
Circulatory Response to Burns
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Adult Respiratory Distress Syndrome (ARDS)
Adult Respiratory Distress Syndrome (ARDS)
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Hyperglycemia in Burns
Hyperglycemia in Burns
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Organ Hypoperfusion
Organ Hypoperfusion
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Metabolic Catabolism in Burns
Metabolic Catabolism in Burns
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End Organ Hypoperfusion
End Organ Hypoperfusion
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Study Notes
Local Anaesthetic Systemic Toxicity (LAST)
- LAST is a life-threatening adverse event that can occur after local anesthetic administration via various routes.
- Symptoms typically develop within 10 minutes but can occur within an hour.
- Local anesthetics are water-soluble salts of lipid-soluble alkaloids. This allows them to dissolve in both water and fat, enabling them to cross cell membranes.
- Local anesthetics target voltage-gated sodium channels, blocking sodium channels and impacting signal transmission to the brain.
- They also affect cardiac conduction, significantly impacting rapid early depolarization.
- Different anesthetics have varying lipid solubility. Those that are more lipid-soluble (like bupivacaine) can cause faster toxicity.
- Awareness of the cumulative nature of local anesthetic agents, especially when multiple doses or agents are administered by different members of the perioperative team, is crucial for preventing LAST.
- Intravascular injection of anesthetics is a significant risk factor for the development of LAST.
- Intravascular markers are recommended if the doses needing administration are potentially toxic.
- Intravascular injection of epinephrine is a potentially life-saving measure, increasing systolic blood pressure by at least 15 mmHg.
- Proper technique, including incremental administration and aspiration before injection, is essential for reducing the risk of intravascular injection.
Systemic Toxicity Mechanism
- Local anesthetics are absorbed into the systemic circulation.
- Absorption rate depends on the administered dose and the vascularity of the surrounding tissue.
- Local anesthetics bind to plasma.
- Saturation leads to increased free drug concentration in the systemic circulation.
- This can trigger organ-specific toxicity, primarily to organs highly perfused with blood, like the brain and heart.
- Brain toxicity manifests as initial excitation (nervousness, confusion, etc.), followed by CNS depression and potentially seizures and respiratory arrest.
- Cardiac toxicity includes ion channel blockade, oxidative phosphorylation inhibition (leading to a lower ATP production), and potential arrhythmias and cardiac arrest.
- Local anesthetics may also cause hypotension, and/or cardiac arrest, and dysrhythmias.
- The rate of absorption depends on the amount of anesthetic administered and the vascularity of the structures around the area.
- Different local anesthetics bind to plasma differently, with some (e.g., bupivacaine) having a high percentage of plasma binding, leading to longer durations of action and higher toxicity risk.
- When plasma is saturated, free drug levels in the systemic circulation rise rapidly, leading to rapid toxicity.
Treatment for LAST
- First priority is discontinuation of the local anesthetic.
- Emergency measures include:
- High-flow oxygen administration to prevent hypoxia and maintain adequate ventilation.
- Establishing intravenous access for rapid treatment with lipid emulsion (20% Intralipid). This is a critical component to remove the free local anesthetic from tissues and into lipids, effectively removing them from the system.
- Intubation and mechanical ventilation if necessary (to correct pH imbalances).
- In cases of circulatory arrest, CPR is the immediate action.
- Administering lipid emulsion (20% Intralipid) is critical for removing free local anesthetic from the tissues and into the lipids, ultimately removing them from the body.
- Use of appropriate medications (like benzodiazepines) to manage seizures, hypotension, or arrhythmias. Use appropriate doses.
- Monitoring of vital signs, including blood pressure, cardiac rhythm, and oxygen saturation, is required throughout treatment and recovery.
- If no circulatory arrest, treat hypotension and arrhythmias with benzodiazepines, avoiding high doses of adrenaline for patients with circulatory arrest.
Prevention of LAST
- Using ultrasound guidance during infiltration of local anesthetics to ensure accurate injection placement, thus limiting intravascular administration.
- Calculate and administer appropriate doses based on the lowest effective dose.
- Incremental administration of doses (e.g., 3-5 mL aliquots, pausing after each administration) to help prevent rapid absorption to reduce systemic absorption.
- Gentle aspiration and check for intravascular leakage before injection.
- Awareness of cumulative nature of local anesthetic agents, and administering doses by different members of the surgical team, is crucial to prevent LAST
- intravascular markers are recommended when the doses requiring administration are potentially toxic.
- Intravascular injection of epinephrine is a potentially life-saving measure, increasing systolic blood pressure by at least 15 mmHg.
- Awareness of the cumulative nature of local anesthetic administration. Specific consideration to the duration of action of individual local anesthetics is also crucial.
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