Shock😊

 

 

ㅤ	Febrile Non hemolytic transfusion reactions
Occurrence	M/c
Within	Within 6 hours
Mechanism	• Graft-versus-host response • Anti-WBC and anti-HLA antibodies • Cytokine accumulation in stored blood
R/F	• Multiparous women donors • FFP donors
Presentation	• Fever and chills • ± Mild dyspnea
Treatment	• Antipyretics • Antihistamines • Stop transfusion if severe
Prevention	• Use leukoreduced product

ㅤ	Anaphylactic	Allergic / Urticarial
Within	Seconds to minutes	Within 2–3 hours
Mechanism	Type I hypersensitivity	Type I hypersensitivity
R/F	Isolated IgA deficiency	ㅤ
Presentation	• Shock • Respiratory distress • Angioedema	• Urticaria • Flushing • Pruritus
Treatment	• Stop transfusion • Epinephrine	• Stop transfusion • IV fluids
Prevention	• Use IgA-deficient plasma • Use washed RBCs	ㅤ

ㅤ	Acute Hemolytic	Delayed Hemolytic
Within	Within 24h	> 24h (usually ~2 weeks)
Mechanism	Type 2 Hypersensitivity • ABO incompatibility • Preformed IgM • Complement-mediated IVH	• Anamnestic IgG response to RBC antigens • Prior sensitization present • Extravascular hemolysis • via reticuloendothelial system
Presentation	• Fever, chills • Flank/back pain • Sense of impending doom • Hemoglobinuria • DIC, renal failure • Coombs’ test positive • Pink plasma	• Mild fever • Hemolytic anemia • Coombs’ test positive • New antibody screening positive
Treatment	• Stop transfusion • IV fluids aggressively	• Supportive care • May need additional transfusion

Leucoreduction filter:

• For Febrile Non hemolytic transfusion reactions

• ↓ Febrile reactions.

• By reducing WBC number.

Other Types of Shock

Shock Type Comparison

Note

• MVO2 > 70% :
• Percentage of oxygen that returns to the heart.
• After being utilized in the body.
• Only ↑ in warm septic shock (distributive shock)

Types of Shock - Further Classification

1. Obstructive shock:
• Mechanical impairment of cardiac filling
• Examples: Tamponade, Pulmonary embolism

2. Distributive shock:
• Blood redistributes to peripheries
• Warm Peripheries
• Mnemonic: Distribute () PVR () via NAS ()
• Examples:
1. Anaphylactic
2. Warm septic
3. Neurogenic

Sepsis and Septic Shock

Terminologies

• Systemic Inflammatory Response Syndrome (SIRS):
• Mediated by IL-1, IL-6, TNF-α.
• 3 or more of following criteria:
• Temperature >38°C or <36°C.
• Heart rate >90 beats/min.
• Respiratory rate >20 breaths/min or PaCO2 <32 torr (4.3 kPa)
• WBC >12000 cells/mm3, <4000 cells/mm3, or >10% immature forms.
• Mnemonic: THRoW () Sir () out

• Sepsis: 
• 2 or more SIRS criteria + known foci of infection.

• MODS (Multiple Organ Dysfunction Syndrome):
• Failure of ≥2 organ systems.

Sepsis 3.0 Guidelines

• SIRS:
• replaced with qSOFA/SOFA.

• Severe sepsis:
• Terminology removed.

• Sepsis:
• Dysregulated host response to infection leading to life-threatening organ dysfunction.

• Septic shock:
• Sepsis leading to hypotension not responding to fluids.
• Need vasopressors & lactate >2 mmol/L.

Quick Sequential Organ Failure Assessment (qSOFA)

• qSOFA Score ≥2 + known foci of infection.

• Score of ≥2 criteria suggests a poor outcome.

Criteria:

• Hypotension (SBP <100 mm Hg).

• Altered mental status.
• GCS < 15

• Tachypnoea (RR ≥22/min).

• Mnemonic:
• Sir (SIRS) → Like 20 (HR 20) year old girl
• but can bring to SOFA (qSOFA) only 22 (HR 22) year old

SOFA Score

• New definition of Sepsis
• Score of 2 ≥ with known foci

Sepsis Bundle

• Completed within 3 hours:
• Measure lactate levels.
• Best lab parameter to monitor tissue perfusion
• Obtain blood cultures.
• Give antibiotics.
• Administer IV fluids.

• Completed within 6 hours:
• Give vasopressors (maintain MAP ≥65 mmHg)
• In PAH → measure MVO2
• Remeasure lactate (if initial levels ↑)

Sepsis Six (Mnemonic: Give 3 + Take 3)

• Give 3:
• IV fluids.
• IV antibiotics.
• Oxygen.

• Take 3:
• Blood culture.
• Urine output.
• Serum lactate.

Neurogenic Shock

Hypovolemic/Hemorrhagic Shock

• M/c type of shock.

Types of Hemorrhage

• a. Overt/visible hemorrhage.

• b. Concealed/Covert hemorrhage:
• Sites:
• Neck.
• Thorax, Abdomen, Pelvis.
• Long bones.

Hemorrhage in Surgery

Classification of Hypovolemic Shock

Management of Hypovolemic Shock

Dynamic fluid response 

• After 1 litre prewarmed IV bolus

• If child < 40kg ⇒ 20 ml/kg

• Diarrhea:
• Ringer's Lactate (RL) is generally preferred.

• Vomiting:
• Normal Saline (NS) is typically preferred.

• Responder:
• PR ↓↓, SBP ↑↑, JVP ↑↑.
• Response: Sustained.

• Transient responder:
• PR ↓, SBP ↑, JVP ↑.
• Response: Reversed in 15-20 mins d/t ongoing loss.

• Non-responder:
• PR ↓↓, SBP ↓↓, JVP ↓.
• Response: Ongoing loss.

Hemorrhage resuscitation:

• Responders:
• Prioritise perfusion.
• → Perfusion targeted resuscitation.

• Ongoing losses / Transient/Non-responders:
• Prioritise coagulation.
• Damage control resuscitation.
• NOT DAMAGE CONTROL SURGERY
• 1:1:1 ⇒ PRBC, Platelet, FFP
• Monitor for coagulopathy → Rotem/TEG

Indicators (for Fluid Requirement)

 

Indicator	CVP	PCWP or Occlusion Pressure
ㅤ	M/c used indicator	Best indicator, more accurate.
Purpose	Right heart function	Left heart function
Equipment	CVC – Central Venous Catheter	PAC – Pulmonary Artery Catheter (Swan-Ganz)
Normal Values	CVP: 0 – 5 cm H₂O.	PCWP: 4 – 12 mmHg.
Fluid Mx	↓ CVP + ↓ BP → Give fluid ↑ CVP + ↓ BP (pump failure) → no fluid.	↑ PCWP → LV dysfunction.
Long-Term Use	For TPN, inotropes, cardiac drugs.	ㅤ
Complication	Common: Arrhythmias.	Common: Arrhythmias. Dreaded: Pulmonary capillary rupture.
Image	• CV Catheter: Triple lumen, 7 Fr (20 cm)	Swan-Ganz catheter assembly

• Urine O/p

Age group	Urine o/p
Adult	0.5 ml/kg/hr
Children	1 ml/kg/hr
Infants	2 ml/kg/hr

Shock Indices

• Shock Index:
• Heart rate / Systolic BP.
• >0.9 = ↑ mortality rate.
• Mnemonic: SH → HS → HR/SBP

• Modified Shock Index:
• Heart rate / Mean arterial pressure (MAP).
• Best index.
• MSI > 1.3 → Hypodynamic state
• Mnemonic: Modified MAP

• Rate over pressure evaluation (ROPE) Index:
• Pulse rate / Pulse pressure.
• >3 = decompensated haemorrhagic shock.
• Mnemonic: ROP → R/P → Rate/PP

End points of Resuscitation

• Systemic perfusion:
• Mixed Venous Oxygen Saturation (MVO2): 
• Best indicator
• Base deficit.
• Serum lactate