Shock. Zeng xuan Hu OCT17

Transcription

1 Shock Zeng xuan Hu OCT17 1

2 Objective Concept Categories Principles of management 2

3 Definition Inadequate tissue perfusion to maintain normal cellular function Not all hypotensive patients are in shock Not all patients in shock are hypotensive young patient, compensated 3

4 Definition Inadequate delivery of O2 (DO2) Inability to utilize deliered O2 4

5 Definition 5

6 Inadequate tissue perfusion-assessment Mental status change Vital sign changes(hypotensive) Oliguria Lactate Base deficit Cr transaminase abnormaity Underlying disease-nf Compensatory machenism -Vasoconstriction, tachy 6

7 Lactate Insufficient O 2 pyruvate lactate dehydrogenase lactate dehydrogenase lactate liver(50%), kidney(30%) The admission level, highest level, time interval to normalize lactate are important prognostic indicators for survival. 7

8 Base deficit The amount of base in mmoles needed to titrate 1 L of whole blood to a ph of 7.40 Mild (3 to 5 mmol/l), moderate (6 to 14 mmol/l), severe (15 mmol/l) Worsen base deficit associated higher mortality Caveat: administration of bicarbonate, hypothermia, hypocapnia

9 Hypovolemic Shock

10 Distributive Shock Anaphylactic Septic Neurogenic Adrenal Insufficiency

11 Cardiogenic Shock Myopathic,arrhyth mic,mechanical

12 Obstructive Shock Cardiac Tamponade Tension Pneumothorax Massive PE

13 Classification of shock Hypovolemic Distributive Obstructive Cardiogenic 13

14 Principle of management ABC Restore tissue perfusion Underlying disease Monitor Supportive care 14

15 Management

16 Vasopressor/inotrop 16

17 Case Study Mr. MS 70 male with PHx of CAD 12 hour post MIS splenectomy in PAR Called for low BP What s your approach?

18 Mr. MS A intubated SaO2 97% on Fi02 of 50% B C BP 80/60, HR 110, Temp 37.2, JVP flat Right IJ in place Combative and confused Cool, mottled extremities Distended abdomen U/O borderline received 3 L NS bolus

19 Mr. MS Findings suggest inadequate tissue perfusion? What type of shock do this pt likely have? differentials? -hypovolemic,obstructive, cardiogenic, distributive Next? 19

20 Mr. MS Resucitation WBC 24, Hb 65 Pl 243 coag N trop 0.5 Lactate 4.2 ABG mild met acidosis CXR bibasilar atelectasis ECG sinus tachycardia, Next? 20

21 Mr. MS Bood transfusion started. Taken immediately OR where bleeding identified from a short gastric artery. Ligated. 1 L blood evacuated. Given 6U prbc, 4U FFP and 5U Plts intraop Brought to PAR and remains intubated Hypovolemic shock

22 Mr. MS( cont.. On POD 2, complains of substernal chest pain and SOB. BP falls to 90/60mmHg with HR 120. Neck veins are distended. Most likely cause?

23 Acute Respiratory Failure Zengxuan Hu OCT17 23

24 Definition Defect in one or both gas exchange functions: oxygenation and carbon dioxide elimination PaO2<60mmHg or PaCO2>45mmHg Derangements in ABGs

25 Types I, Hypoxemic II, hypercapnic III, Perioperative I V, Shock Mechanism V/ Q mismatch Alveolar ventilation Atelectasis Hypoperfusion Etiology Airspace flooding 1. CNS drive 2. N-M coupling FRC 1. Cardiogenic 2. hypovolemic 3. Septic Clinical Description 1. ARDS 2. Alveolar hemorrhage 1. Overdose/CNS injury 2. Myasthenia gravis, upper abdominal incision, anesthesia 1. Myocardial infarct 2. endotoxemia, bacteremia

26 Mechanism Hypoventilation V/Q mismatch Shunt Diffusion abnormality

27 Hypoventilation Won t breathe resp drive Brainstem stroke Sedatives Can t breathe NM system Lung/airway Chest wall/pleura PaCO2 and PaO2 Alveolar arterial PO2 gradient is normal

28 V/Q mismatch Capillary flow excessive relative to vent V/Q ratio < 1 Small airway occlusion-asthma Alveoli-collapse,fluid, excessive capillary blood flow Admin. of 100% O2 eliminate hypoxemia

29 Shunt The deoxygenated blood bypasses the alveoli and mixes with oxygenated blood hypoxemia Persistent of hypoxemia despite 100% O2 inhalation Hypercapnia occur when shunt is excessive > 50%

30 Intracardiac Causes of Shunt Right to left shunt Pulmonary Fallot s tetralogy Eisenmenger s syndrome A/V malformation Pneumonia Atelectasis/collapse Pulmonary hemorrhage Pulmonary contusion

31 Diffusion Abnormality Abnormality of the alveolar membrane the number of the alveoli ARDS Fibrotic lung disease

32 Presentations of hypoxia Respiratory tachypnea, dyspnea CNS effects Impaired judgment and cognitive function Depressed brainstem function-consciousness Cardiovascular effects Arrhythmia Myocardial depression Hypotension, Shock

33 Presentations of hypercapnia CNS-mental status change Anxiety, irritability Confusion Lethargy, Stupor, coma Respiratory shallow breathing Cardiovascular effects Hypotension Ventricular irritability

34 ABG CBC, Hb Anemia Polycythemia Urea, Creatinine Electrolytes (K, Mg, Ph) Troponin TSH Diagnosis of RF -Investigations tissue hypoxemia chronic RF Aggravate RF MI Hypothyroidism

35 Chest x ray Echocardiography Diagnosis of RF Investigations PFT- (FEV1/ FVC ratio) Decrease Increase Pulmonary edema ARDS Cardiogenic ARDS Rt ventricular hypertrophy in CRF Airflow obstruction Restrictive lung disease

36 Investigations ECG cardiac cause of RF Arrhythmia due to hypoxemia & severe acidosis Right heart catheterization Pulmonary capillary wedge pressure (PCWP) Normal ARDS (<18 mmhg) Increased Cardiogenic pulmonary edema

37 Hypoxemic Respiratory Failure Yes Hypoventilation Is PaCO2 increased? No (PAO2 - PaO2)? (PAO2 - PaO2) Yes No Hypoventilation alone Respiratory drive Neuromuscular dz Hypovent plus another mechanism Shunt Is low PO2 correctable with O2? No Yes V/Q mismatch Inspired PO2 High altitude FIO2

38 Hypercapnic Respiratory Failure PaCO2 >45mmHg Not compensation for metabolic alkalosis (PAO2 - PaO2) normal Alveolar Hypoventilation increased V/Q abnormality PI max Nl VCO2 VCO2 Central Hypoventilation Neuromuscular Disorder V/Q Abnormality Hypermetabolism Overfeeding

39 Management A B C, identify reversible causes Endotracheal intubation: Indications Severe Hypoxemia Altered mental status Severe acidosis

40 Mechanical ventilation Increase PaO2 Lower PaCO2 Rest respiratory ms (respiratory ms fatigue)

41 Noninvasive Ventilatory support (IPPV) Mild to moderate RF Intact airway, Alert, normal airway protective reflexes Nasal or full face mask, BPAP,CPAP Improve oxygenation, Reduce work of breathing Increase cardiac output

42 Treating Underlying Disease Antibiotics Pneumonia Infection Bronchodilators (COPD) Salbutamol reduce bronchospasm airway resistance Anticholinergics (COPD) Ibratropium bromide inhibit vagal tone relax smooth ms

43 Hemodynamic Support Fluids and electrolytes Maintain fluid balance and avoid fluid overload Reduction of O2 requirements Vasopressor, inotropes The maintenance of cardiac output is crucial for O2 delivery Diuretics (pulmonary edema) Frusemide, Metalozone

44 Ventilation strategy Recruitment maneuvers Prone Inhaled nitric oxide High frequency oscillation 44

45 Case study A 58 M with no known medical histoy admitted for gallstone pancreatitis. Receives supportive care. POA 2 getting worse.sob. Tachypneic 35/min. Shallow breathing. Using accessory muscles. On 70 % O2 with mask. Anxious. BP 110/60, HR 90, Temp 37.5, GCS 15 ABG PH 7.34, Po2 40, Pco2 40, Diminished breath sounds bilaterally with scattered rhonchi CXR: bilateral nonsegmental infiltrates. no effusion or PTX. What findings suggest RF? What form of RF? Does he require intubation?

46 CXR-bilateral infiltration 46

47 Case study Diagnosis ARF type 1 ARDS/Acute lung injury DD: Aspiration, pnuemonia, PE, cardiogenic pulmonary edema, lung contusion(trauma) Intubation:severe hypoxemia, tachypneicimpending respiratory arrest, underlying disease process not clear.

48 Case study 57 F with Myasthenia Gravis x 1 yr on MESTINO(pyridostigmine) 40mg daily Depression with borderline personality feature. Presents to ER with 2 week s general weakness, mild SOB x 2 days. In no cute distress. Vitals N. SaO2 95% with 4 L NP VC x 3 showed 800ml. ABG 7.35/48/31. Po2 73. CXR possible right side pneumonia. What form of RF? Management?