Shock bs thao1

Shock

1Dr Mai Duc Thao. ED. Friendship Hospital.

Ha noi 2013

Is This Patient in Shock?• Patient looks ill

• Altered mental status

• Skin cool and mottled or hot

and flushed

• Weak or absent peripheral

pulses

• SBP <90

• Tachycardia

Yes! These are all signs and symptoms of shock

2Dr Mai Duc Thao. ED. Friendship Hospital. Ha noi 2013

Dr Mai Duc Thao. ED. Friendship Hospital. Ha noi 2013

• A 68 yo M with presents to the ED with abrupt onset of

diffuse abdominal pain with radiation to his low back. The pt

is hypotensive, tachycardic, afebrile (no fever), with cool but

dry skin.

• An 81 yo F ED with altered mental status. She is febrile to

39.4, hypotensive with a widened pulse pressure, tachycardic,

with warm extremities

Case

Dr Mai Duc Thao. ED. Friendship Hospital. Ha noi 2013 4

• A 41 yo M presents to the ED after an MVC complaining of

decreased sensation below his waist and is now hypotensive,

bradycardic, with warm extremities

Case

• A 55 yo M DM presents with “crushing” substernal chest

pain, diaphoresis, hypotension, tachycardia and cool,

clammy extremities

Objectives

Definition Approach to the hypotensive patient Types Specific treatments


Definition of Shock• A complex clinical syndrome caused by an acute

failure of circulatory function and characterized by inadequate tissue and organ perfusion.

• Inadequate oxygen delivery to meet metabolic demands

• Results in global tissue hypoperfusion and metabolic acidosis

• Shock can occur with a normal blood pressure and hypotension can occur without shock


DEFINATION Shock give rise to systemic hypoperfusion caused by reduction either in

cardiac output or in effective circulatory blood volume. End results are : Hypotension

Tissue hypoperfusion

Cellular hypoxia

Reversible injury

Irreversible injury with persistent of shock

End organ dysfunction

Death

Determinants of Oxygen Delivery

OxygenDelivery = Content (CaO2) x Cardiac output (CO)

CaO2 = 1.34 (Hgb x SaO2) + (PaO2 x 0.003) SaO2: Oxygen saturation Hgb: Hemoglobin concentration PaO2: partial pressure Oxygen in plasma

↳ To improve Oxygen content Increase Hemoglobin concentration Increase saturation

8Dr Mai Duc Thao. ED. Friendship Hospital.Ha noi 2013

CaO2 is arterial oxygen content (in milliliters per deciliter), Hb is hemoglobin concentration (in grams per deciliter), SaO2 is hemoglobin saturation of arterial blood (in percent), and PaO2 is partial pressure of dissolved oxygen in arterial blood (in millimeters of mercury).

Determinants of Oxygen Delivery Cardiac output

C.O = Heart rate x stroke volume

↳ To improve Cardiac output

Increase Heart rate

Increase Stroke Volume

Preload – volume of blood in the ventricle

Afterload – resistance to contraction

Contractility – force applied


Understanding Shock autonomic responses ?

• Inadequate systemic oxygen delivery activates autonomic

responses to maintain systemic oxygen delivery

Sympathetic nervous system:

• Epinephrine, dopamine, and cortisol release

• Causes vasoconstriction, increase in HR, and

increase of cardiac contractility (cardiac output)

Renin-angiotensin axis

• Water and sodium conservation and vasoconstriction

• Increase in blood volume and blood pressure10Dr Mai Duc Thao. ED. Friendship Hospital.

Ha noi 2013

Myocardial Contractility Stroke Volume Preload Cardiac Output Afterload

Blood Pressure Heart Rate Systemic Vascular Resistance

Textbook of Pediatric Advanced Life Support, 1988Textbook of Pediatric Advanced Life Support, 1988


Understanding Shock

Understanding Shock• Cellular responses to decreased systemic oxygen delivery

• ATP depletion → ion pump dysfunction (Na+, K+ATPase)

• Cellular edema

• Hydrolysis of cellular membranes and cellular death

• Goal is to maintain cerebral and cardiac perfusion

• Vasoconstriction of splanchnic, musculoskeletal, and renal

blood flow

Leads to systemic metabolic lactic acidosis that

overcomes the body’s compensatory mechanisms 12Dr Mai Duc Thao. ED. Friendship Hospital.

Ha noi 2013

Global Tissue Hypoxia

• Endothelial inflammation and disruption

• Inability of O2 delivery to meet demand, Anaerobic

respiration

Result:

• Lactic acidosis

• Cardiovascular insufficiency

• Increased metabolic demands13Dr Mai Duc Thao. ED. Friendship Hospital.

Ha noi 2013

Multiorgan DysfunctionSyndrome (MODS)

• Progression of physiologic effects as shock ensues

• Cardiac depression

• Respiratory distress

• Renal failure

• DIC

• Result is end organ failure


• ABCs

• Cardiorespiratory monitor

• Pulse oximetry

• Supplemental oxygen

• IV access

• ABG, labs

• Foley catheter

• Vital signs including rectal temperature

Approach to the Patient in Shock


Approach to the Patient in Shock

• History• Recent illness• Fever• Chest pain, SOB• Abdominal pain• Comorbidities• Medications• Toxins/Ingestions• Recent hospitalization or

surgery• Baseline mental status

• Physical examination• Vital Signs• CNS – mental status• Skin – color, temp, rashes,

sores• Heart sounds• Resp – lung sounds, RR,

oxygen sat, ABG• GI – abd pain…• Renal – urine output


Diagnosis

• Physical exam (VS, mental status, skin color, temperature, pulses, etc)

• Infectious source• Labs:

• CBC• Chemistries• Lactate• Coagulation studies• Cultures• ABG


Further Evaluation• CT of head/sinuses

• Lumbar puncture

• Wound cultures

• Acute abdominal series

• Abdominal/pelvic CT or US

• Cortisol level

• Fibrinogen, FDPs, D-dimer


Treatment

• ABCDE

• Airway

• control work of Breathing

• optimize Circulation

• assure adequate oxygen Delivery

• achieve End points of resuscitation


Airway• Determine need for intubation but remember: intubation

can worsen hypotension

• Sedatives can lower blood pressure

• Positive pressure ventilation decreases preload

May need volume resuscitation prior to intubation to

avoid hemodynamic collapse


Control Work of Breathing

• Respiratory muscles consume a significant amount of

oxygen

• Tachypnea can contribute to lactic acidosis

• Mechanical ventilation and sedation decrease WOB and

improves survival


Optimizing Circulation• Isotonic crystalloids

• Titrated to:

• CVP 8-12 mm Hg

• Urine output 0.5 ml/kg/hr (30 ml/hr)

• Improving heart rate

• May require 4-6 L of fluids

• No outcome benefit from colloids


Maintaining Oxygen Delivery• Decrease oxygen demands

• Provide analgesia and anxiolytics to relax muscles and

avoid shivering

• Maintain arterial oxygen saturation/content

• Give supplemental oxygen

• Maintain Hemoglobin > 10 g/dL

• Serial lactate levels or central venous oxygen saturations to

assess tissue oxygen extraction


End Points of Resuscitation• Goal of resuscitation is to maximize survival and minimize

morbidity

• Use objective hemodynamic and physiologic values to guide

therapy

• Goal directed approach

• Urine output > 0.5 mL/kg/hr

• CVP 8-12 mmHg

• MAP 65 to 90 mmHg

• Central venous oxygen concentration > 70%24Dr Mai Duc Thao. ED. Friendship Hospital.

Ha noi 2013

Persistent Hypotension• Inadequate volume resuscitation

• Pneumothorax

• Cardiac tamponade

• Hidden bleeding

• Adrenal insufficiency

• Medication allergy


Practically Speaking….

• Keep one eye on these patients

• Frequent vitals signs:

• Monitor success of therapies

• Watch for decompensated shock

• Let your nurses know that these patients are sick!



First aid


First aid

Types of Shock • Hypovolemic

• Septic

• Cardiogenic

• Anaphylactic

• Neurogenic, trauma

• Obstructive

• poison


Classification of Shock

Hypovolemic Shock (#1 cause world wide)Dehydration, hemorrhagic (Hemorrhagic, nonhemorrhagic) Cardiogenic Shock

Pump failure, obstructive, L-R shunt Ischemic, Myopathic, Mechanical, Arrhythmia

Distributive Shock Neurogenic (spinal shock), Anaphylaxis, septic

Obstructive Massive Pulmonary embolism, Tension pneumothorax Cardiac tamponade, Constrictive pericarditis Septic Shock – All of the above



Classification of Shock

An Introduction to

ClinicalEmergencyMedicineSwaminatha V. Mahadevan, MD , FACEP, FAAEM

Associate Chief, Division of Emer gency MedicineAssistant Professor of Surgery (Emergency Medicine)Stanford University School of MedicineEmergency Department Medical DirectorMedical Student Clerkship Dir ector Stanford University Medical Center, Stanford, CA

G us M. G armel, MD , FACEP, FAAEM

Co-Program Director, Stanford/Kaiser Emergency Medicine ResidencyClinical Associate Professor of Surgery (Emergency Medicine)Stanford University School of MedicineSenior Staff Emergency Physician, The Permanente Medical Gr oupClerkship Director for Medical Students and Rotating InternsKaiser Permanente Medical Center , Santa Clara, CA

Cambridge University Press 2005

Physiologic parameters in shock states


What Type of Shock is This?

• 68 yo M with presents to the ED with abrupt onset of diffuse

abdominal pain with radiation to his low back. The pt is

hypotensive, tachycardic, afebrile (no fever), with cool but

dry skin.

Hypovolemic Shock


34


35

• Tachycardia and hypotension.

• Cool and frequently cyanotic extremities.

• Collapsed neck veins.

• Oliguria or anuria.

• Rapid correction of signs with volume infusio

ESSENTIALS OF DIAGNOSIS



Mild (<20%) Moderate(20-40%) Severe(>40%)

Cold extremitiesDiaphoresisAnxiety

Same +TachycardiaTachypnoeaOliguriaPostural -hypotension

Same +HypotensionMental status deterioration

Hypovolemic Shock


• An 81 yo F ED with altered mental status. She is febrile to

39.4, hypotensive with a widened pulse pressure, tachycardic,

with warm extremities

Septic



Manifestation of excessive & inflammatory response of

endogenous immune mechanism two or more of the following:– T >38 or <36 C– HR >90 bpm – RR >20/min or PaCO2 <32 mmHg– WBC >12,000 or <4,000 cells/ or >10% bands

Sepsis is SIRS with established focus of infection

Septic shock - severe sepsis unresponsive to continuous fluid

infusion and inotropes

Septic shock

Definition by American College of Chest Physicians/Society of Critical Care Medicine

SCCM/ESICM/ACCP/ATS/SIS International Sepsis Definitions Conference, Levy MM et al., Crit. Care Med. 2003, 31(4): 1250-1256)

A clinician, armed with the sepsis bundles, attacks the three heads of severe sepsis: hypotension, hypoperfusion, and organ dysfunction.

Crit Care Med. 2004;320(Suppl):S595-S597

What Type of Shock is This?• A 55 yo M DM presents with “crushing” substernal chest

pain, diaphoresis, hypotension, tachycardia and cool,

clammy extremities

Cardiogenic shock



• Decreased urine output.

• Impaired mental function.

• Cool extremities.

• Distended neck veins.

• Hypotension with evidence of peripheral and pulmonary

venous congestion.

• Acute myocardial infarction most common cause



Circulatory pump failure in setting of adequate

vascular volume

Sustained hypotension SBP < 90 mm Hg for at least

30 minutes

CI < 2.2 L/min/m2

PAWP >15mmHg

Surgical importance in patients with chest trauma for

Tamponade

Tension pneumothorax

Cardiogenic shock


What Type of Shock is This?• A 34 yo F presents to the ED after dining at a restaurant where

shortly after eating the first few bites of her meal, became anxious,

diaphoretic, began wheezing, noted diffuse pruritic rash, nausea,

and a sensation of her “throat closing off”. She is currently

hypotensive, tachycardic and ill appearing.

Anaphalactic46Dr Mai Duc Thao. ED. Friendship Hospital.

Ha noi 2013



•Cutaneous flushing, pruritus.

•Abdominal distention, nausea, vomiting, diarrhea.

•Airway obstruction owing to laryngeal edema.

•Bronchospasm, bronchorrhea, pulmonary edema.

•Tachycardia, syncope, hypotension.

•Cardiovascular collapse.

Management of anaphylaxis Anaphylaxis is an acute medical emergency. The

immediate management includes: preventing further contact with the allergen (e.g. removal of

bee sting) ensuring airway patency administration of oxygen restoration of blood pressure (laying the patient flat,

intravenous fluids) prompt administration of adrenaline (epinephrine). Intravenous antihistamines (chlorphenamine 10-20 mg i.m.

or slow i.v. injection), which limit ongoing inflammation. Corticosteroids (hydrocortisone 100-300 mg) prevent late-

phase symptoms in severely affected patients.


What Type of Shock is This?• A 41 yo M presents to the ED after an MVC complaining of

decreased sensation below his waist and is now hypotensive,

bradycardic, with warm extremities

Neurogenic shock



• Preceded by trauma or spinal anesthesia.

• Hypotension with tachycardia.

• Cutaneous warmth and flushing in the

denervated area.

• Venous pooling.


Neurogenic Shock



• A 24 yo M presents to the ED after an MVC c/o chest pain and

difficulty breathing. On PE, you note the pt to be tachycardic,

hypotensive, hypoxic, and with decreased breath sounds on left

Obstructive


Obstructive Shock


HypothermiaHypothermia BradycardiaBradycardia HypotensionHypotension Respiratory depressionRespiratory depression Constricted pupilsConstricted pupils CNS depressionCNS depression

Narcotic - toxicNarcotic - toxic


ABCABC Consider thiamine, dextrose, naloxone if depressed GCSConsider thiamine, dextrose, naloxone if depressed GCS Prevent further absorptionPrevent further absorption

Decontaminate eyes, clothes, skin, hair if appropriate eyes, clothes, skin, hair if appropriate Activated charcoal + sorbitol (if < 1 hour from ingestion)+ sorbitol (if < 1 hour from ingestion) Gastric lavage (if < 1 hour from ingestion and life-threatening drug or dose) (if < 1 hour from ingestion and life-threatening drug or dose)

In general not usedIn general not used Whole bowel irrigation for for ““body packingbody packing”” illicit drugs illicit drugs

In general not usedIn general not used

Enhance eliminationEnhance elimination Forced diuresis and urinary alkalinisation (salicylates and barbiturates)(salicylates and barbiturates) Multiple dose activated charcoal 0.5 g/kg every 2-4 hours0.5 g/kg every 2-4 hours

binds toxin and interrupts enterohepatic recirculationbinds toxin and interrupts enterohepatic recirculation mainly life-threatening ingestion of carbamazepine, dapsone, phenobarbital, quinine or theophyllinemainly life-threatening ingestion of carbamazepine, dapsone, phenobarbital, quinine or theophylline

Extracorporeal removal (for active metabolites, delayed toxicity or poor organ clearance)(for active metabolites, delayed toxicity or poor organ clearance) HaemodialysisHaemodialysis - low MW (<500 d), soluble, low Vd (< 1L/kg) e.g. methanol, ethylene glycol, - low MW (<500 d), soluble, low Vd (< 1L/kg) e.g. methanol, ethylene glycol,

salicylates, lithiumsalicylates, lithium HaemoperfusionHaemoperfusion - e.g theophylline, phenobarbital, phenytoin, carbamazepine, paraquat - e.g theophylline, phenobarbital, phenytoin, carbamazepine, paraquat Haemofil t rat ionHaemofi l t rat ion for large Vd and extensive tissue bound toxins but removes virtually all drugs for large Vd and extensive tissue bound toxins but removes virtually all drugs

AntidotesAntidotes

General ManagementGeneral Management




References Tintinalli. Emergency Medicine. 6th

edition Rivers et al. Early Goal-Directed

Therapy in the Treatment of Severe Sepsis and Septic Shock. NEJM 2001; 345(19):1368.

59Dr Mai Duc Thao. ED. Friendship

Hospital. Ha noi 2013

Health & Medicine

Shock bs thao1