- •ICU Protocols
- •Preface
- •Acknowledgments
- •Contents
- •Contributors
- •1: Airway Management
- •Suggested Reading
- •2: Acute Respiratory Failure
- •Suggested Reading
- •Suggested Reading
- •Website
- •4: Basic Mechanical Ventilation
- •Suggested Reading
- •Suggested Reading
- •Websites
- •Suggested Reading
- •Websites
- •7: Weaning
- •Suggested Reading
- •8: Massive Hemoptysis
- •Suggested Reading
- •9: Pulmonary Thromboembolism
- •Suggested Reading
- •Suggested Reading
- •Websites
- •11: Ventilator-Associated Pneumonia
- •Suggested Readings
- •12: Pleural Diseases
- •Suggested Reading
- •Websites
- •13: Sleep-Disordered Breathing
- •Suggested Reading
- •Websites
- •14: Oxygen Therapy
- •Suggested Reading
- •15: Pulse Oximetry and Capnography
- •Conclusion
- •Suggested Reading
- •Websites
- •16: Hemodynamic Monitoring
- •Suggested Reading
- •Websites
- •17: Echocardiography
- •Suggested Readings
- •Websites
- •Suggested Reading
- •Websites
- •19: Cardiorespiratory Arrest
- •Suggested Reading
- •Websites
- •20: Cardiogenic Shock
- •Suggested Reading
- •21: Acute Heart Failure
- •Suggested Reading
- •22: Cardiac Arrhythmias
- •Suggested Reading
- •Website
- •23: Acute Coronary Syndromes
- •Suggested Reading
- •Website
- •Suggested Reading
- •25: Aortic Dissection
- •Suggested Reading
- •26: Cerebrovascular Accident
- •Suggested Reading
- •Websites
- •27: Subarachnoid Hemorrhage
- •Suggested Reading
- •Websites
- •28: Status Epilepticus
- •Suggested Reading
- •29: Acute Flaccid Paralysis
- •Suggested Readings
- •30: Coma
- •Suggested Reading
- •Suggested Reading
- •Websites
- •32: Acute Febrile Encephalopathy
- •Suggested Reading
- •33: Sedation and Analgesia
- •Suggested Reading
- •Websites
- •34: Brain Death
- •Suggested Reading
- •Websites
- •35: Upper Gastrointestinal Bleeding
- •Suggested Reading
- •36: Lower Gastrointestinal Bleeding
- •Suggested Reading
- •37: Acute Diarrhea
- •Suggested Reading
- •38: Acute Abdominal Distension
- •Suggested Reading
- •39: Intra-abdominal Hypertension
- •Suggested Reading
- •Website
- •40: Acute Pancreatitis
- •Suggested Reading
- •Website
- •41: Acute Liver Failure
- •Suggested Reading
- •Suggested Reading
- •Websites
- •43: Nutrition Support
- •Suggested Reading
- •44: Acute Renal Failure
- •Suggested Reading
- •Websites
- •45: Renal Replacement Therapy
- •Suggested Reading
- •Website
- •46: Managing a Patient on Dialysis
- •Suggested Reading
- •Websites
- •47: Drug Dosing
- •Suggested Reading
- •Websites
- •48: General Measures of Infection Control
- •Suggested Reading
- •Websites
- •49: Antibiotic Stewardship
- •Suggested Reading
- •Website
- •50: Septic Shock
- •Suggested Reading
- •51: Severe Tropical Infections
- •Suggested Reading
- •Websites
- •52: New-Onset Fever
- •Suggested Reading
- •Websites
- •53: Fungal Infections
- •Suggested Reading
- •Suggested Reading
- •Website
- •55: Hyponatremia
- •Suggested Reading
- •56: Hypernatremia
- •Suggested Reading
- •57: Hypokalemia and Hyperkalemia
- •57.1 Hyperkalemia
- •Suggested Reading
- •Website
- •58: Arterial Blood Gases
- •Suggested Reading
- •Websites
- •59: Diabetic Emergencies
- •59.1 Hyperglycemic Emergencies
- •59.2 Hypoglycemia
- •Suggested Reading
- •60: Glycemic Control in the ICU
- •Suggested Reading
- •61: Transfusion Practices and Complications
- •Suggested Reading
- •Websites
- •Suggested Reading
- •Website
- •63: Onco-emergencies
- •63.1 Hypercalcemia
- •63.2 ECG Changes in Hypercalcemia
- •63.3 Superior Vena Cava Syndrome
- •63.4 Malignant Spinal Cord Compression
- •Suggested Reading
- •64: General Management of Trauma
- •Suggested Reading
- •65: Severe Head and Spinal Cord Injury
- •Suggested Reading
- •Websites
- •66: Torso Trauma
- •Suggested Reading
- •Websites
- •67: Burn Management
- •Suggested Reading
- •68: General Poisoning Management
- •Suggested Reading
- •69: Syndromic Approach to Poisoning
- •Suggested Reading
- •Websites
- •70: Drug Abuse
- •Suggested Reading
- •71: Snakebite
- •Suggested Reading
- •72: Heat Stroke and Hypothermia
- •72.1 Heat Stroke
- •72.2 Hypothermia
- •Suggested Reading
- •73: Jaundice in Pregnancy
- •Suggested Reading
- •Suggested Reading
- •75: Severe Preeclampsia
- •Suggested Reading
- •76: General Issues in Perioperative Care
- •Suggested Reading
- •Web Site
- •77.1 Cardiac Surgery
- •77.2 Thoracic Surgery
- •77.3 Neurosurgery
- •Suggested Reading
- •78: Initial Assessment and Resuscitation
- •Suggested Reading
- •79: Comprehensive ICU Care
- •Suggested Reading
- •Website
- •80: Quality Control
- •Suggested Reading
- •Websites
- •81: Ethical Principles in End-of-Life Care
- •Suggested Reading
- •82: ICU Organization and Training
- •Suggested Reading
- •Website
- •83: Transportation of Critically Ill Patients
- •83.1 Intrahospital Transport
- •83.2 Interhospital Transport
- •Suggested Reading
- •84: Scoring Systems
- •Suggested Reading
- •Websites
- •85: Mechanical Ventilation
- •Suggested Reading
- •86: Acute Severe Asthma
- •Suggested Reading
- •87: Status Epilepticus
- •Suggested Reading
- •88: Severe Sepsis and Septic Shock
- •Suggested Reading
- •89: Acute Intracranial Hypertension
- •Suggested Reading
- •90: Multiorgan Failure
- •90.1 Concurrent Management of Hepatic Dysfunction
- •Suggested Readings
- •91: Central Line Placement
- •Suggested Reading
- •92: Arterial Catheterization
- •Suggested Reading
- •93: Pulmonary Artery Catheterization
- •Suggested Reading
- •Website
- •Suggested Reading
- •95: Temporary Pacemaker Insertion
- •Suggested Reading
- •96: Percutaneous Tracheostomy
- •Suggested Reading
- •97: Thoracentesis
- •Suggested Reading
- •98: Chest Tube Placement
- •Suggested Reading
- •99: Pericardiocentesis
- •Suggested Reading
- •100: Lumbar Puncture
- •Suggested Reading
- •Website
- •101: Intra-aortic Balloon Pump
- •Suggested Reading
- •Appendices
- •Appendix A
- •Appendix B
- •Common ICU Formulae
- •Appendix C
- •Appendix D: Syllabus for ICU Training
- •Index
Mechanical Ventilation |
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Praveen Khilnani and Rajiv Uttam |
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A 2-year-old girl with fever and cough for the past 4 days was admitted to the hospital with worsening respiratory distress and tachypnea. Her SpO2 on room air was 83%. She was put on oxygen at 12 L/min. In spite of high ßow of oxygen, SpO2 was still 85Ð88%. Chest X-ray showed ßuffy shadows bilaterally. In view of clinical exhaustion, severe hypoxemia, and evidence of respiratory acidosis on blood gas, she was intubated.
Mechanical ventilation is the process of delivery of tidal volume with a set FiO2 at a certain rate by presetting the peak inspiratory pressure (pressure ventilation) or tidal volume (volume ventilation) on the ventilator, with a purpose to remove CO2 from lungs and deliver oxygen to the pulmonary capillaries. This is based on gradient of mean airway pressure in the alveoli resulting from delivery of peak inspiratory pressure (PIP) and positive end-expiratory pressure (PEEP) for the entire duration of the respiratory cycle (inspiratory time and expiratory time).
Step 1: Initial resuscitation
¥Patient is resuscitated and rapid sequence intubation (RSI) is planned within 1 min (Table 85.1 and Fig. 85.1).
¥The main purpose of RSI is to avoid positive-pressure ventilation by bag and mask and prevent gastric inßation in patients at risk of aspiration.
P. Khilnani, M.D., F.C.C.M. (*)
Pediatric Critical Care and Pulmonology, BL Kapur Memorial Hospital, New Delhi, India e-mail: khilnanip@hotmail.com
R. Uttam, M.R.C.P.
Pediatric Critical Care and Pulmonology, Max Superspeciality Hospitals, Patparganj,
Delhi, India
R. Chawla and S. Todi (eds.), ICU Protocols: A stepwise approach, |
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DOI 10.1007/978-81-322-0535-7_85, © Springer India 2012 |
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P. Khilnani and R. Uttam |
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Table 85.1 The eight ÒPÓs of RSI |
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Time |
Action |
Zero minus 10 min |
Preparation |
Zero minus 5 min |
Preoxygenation |
Zero minus 3 min |
Pretreatment |
Time zero |
Paralysis with induction |
Zero plus 20Ð30 s |
Protection and positioning |
Zero plus 45 s |
Placement |
Zero plus 45 s |
Proof |
Zero plus 1 min |
Postintubation management |
Rapid sequence intubation
Objective:to secure the airway rapidly and prevent aspiration of gastric contents
Steps
•Preparation
•Preoxygenation
•Pretreatment
•Paralysis with induction
•Protection and positioning
•Placement with proof
•Post intubation management
Paralysis with induction
•Rapidly acting induction agent
Midazolam: 0.1–0.5 mg/kg Ketamine: 1–3 mg/kg
•Rapidly acting neuromuscular paralyticagent:
Succinylcholine: 1–2 mg/kg
Rocuronium: 1 mg/kg
Preparation
•Assess patient: anatomy (short neck, micrognatghia), habitus, injuries
•Establish IV
•Monitor SpO2
•Monitor ECG, BP continuously
•Assemble equipment: tube and stylet, test cuff
•Choose laryngoscope blade, test light
Protection and positioning Watch for apnea within 20 seconds
•Bag mask ventilation
•Sellick’s maneuver Cricoid cartilage pressure Helps prevent aspiration
Continue until tube is placed or paralysis worn off
No bagging during RSI after induction
Postintubation management
•Secure tube
•Recheck vital signs
Heart rate Blood pressure
Postintubation management
•Medications
•Continued paralysis
Vecuronium: 0.1 mg/kg
Sedation
• Benzodiazepines
Opioids
Preoxygenation: Pre oxygenate for full 3 minutes, to wash all the nitrogen out of the lungs and create a reservoir of O2
Pretreatment
•Often optional step
•Mitigate adverse reactions
•Lidocaine(1 mg/kg)
•Opioids
•Atropine for children
<8 years
• Defasciculating dose of paralytics
Placement with proof
Tube placement
•Test jaw for flaccidity 45 seconds after succinylcholine
•Insert ETT
•Sellick’s maneuver discontinued after cuff is
inflated
Confirm tube placement
ETCO2 Breath sounds Chest rise Chest X-ray
Fig. 85.1 Rapid sequence intubation protocol
85 Mechanical Ventilation |
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¥Bag-and-mask ventilation may be necessary in apneic patients or those with ineffective spontaneous breathing.
¥In such patients, SellickÕs maneuver is performed to prevent air entering into stomach, and gentle AMBU bagging can be done.
Step 2: Initiation and ventilator management
Monitor the status of oxygenation and ventilation and titrate ventilator parameters accordingly (Fig. 85.2).
A.Initial ventilator settings: pressure limited
¥ModeÑpressure control.
¥FiO2Ñstart with 1 and wean down to get good SpO2 (>90%).
¥Optimal positive end-expiratory pressure (PEEP)Ñto achieve adequate alve-
olar recruitment so that saturations are maintained at minimum FiO2 (<0.6) and compliance is best with no hemodynamic compromise.
¥Respiratory rateÑnormal for age (adjust if there is air trapping).
¥Pressure control above PEEP (peak inspiratory pressure [PIP]-PEEP)Ñso that tidal volume equal to 6Ð8 mL/kg is delivered with adequate chest rise.
¥Inspiratory timeÑnormal for age, 0.4 s for neonates, 0.5Ð0.6 s for infants, 0.6Ð0.8 s for toddlers, and 0.9Ð1.0 s for older children (adjust in case of air trapping or severe acute respiratory distress syndrome [ARDS]).
B.Volume limited
¥ModeÑvolume control
¥Tidal volumeÑ6Ð8 mL/kg of ideal body weight, look for adequate chest rise
¥Inspiratory timeÑnormal for age (adjust in case of air trapping or severe ARDS)
¥Optimal PEEPÑadequate alveolar recruitment so that saturations are main-
tained at minimum FiO2 (<0.6) and compliance is best with no hemodynamic compromise
¥Respiratory rateÑnormal for age (adjust if there is air trapping)
¥FiO2Ñto get good SpO2 (>90%)
C.Sedation and analgesia
¥Most patients can be managed with adequate sedation and analgesia without muscle relaxants. Muscle relaxants should never be started without adequate sedation.
¥Midazolam and morphine or fentanyl are used for most of the cases. In case of speciÞc scenarios, other agents can be tried.
¥Morphine is not preferred in hemodynamic instability and wheezing. Ketamine can be used.
¥Midazolam is not preferred in severe hemodynamic instability and liver failure.
¥Ketamine is preferred in shock and wheezing. Ketamine is not used in raised intracranial pressure.
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P. Khilnani and R. Uttam |
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Choose conventional |
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ventilation |
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Initiation |
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Choose mode |
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Choose initial settings |
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Set trigger sensitivity |
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Set alarm limits |
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Select sedation and analgesia |
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Monitor SpO2, HR, and BP |
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ABG (1 hour after starting then |
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Chest xray |
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Troubleshooting |
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Displacement |
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Respiratory care protocol |
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Obstruction |
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Head end elevation |
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Pneumothorax |
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Position change 2-hourly |
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Equipment failure |
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Suction (in line or otherwise) |
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as needed |
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Chest physiotherapy if |
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required |
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Increase PEEP increase FiO2 |
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• NO IMPROVEMENT |
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Choose HFOV |
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Table 85.2 |
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•Increase MAP, FiO2 for poor oxygenation
•Increase amplitude and decrease frequency for high PaCO2
•MAP - 2 Cm H2O above conventional
•FiO2 –minimum to keep saturations above 88%
•Frequency–according to age ( 10-12 for newborns, 8-10 for small children, 6-8 for big children)
•Amplitude and power-for wiggle up to groin or mid thigh
•Inspiratory time – 33%, bias flow>25 L/min
Do ABG and CXR one hour after starting and after every major change in settings
Make changes according to SPO2, ABG
Wean FiO2, MAP as condition improves
Switch to conventional when MAP <20, FiO2 0.4
Spontaneous breathing trial
Extubation
Fig. 85.2 Ventilator management protocol
Step 3: Change settings according to arterial blood gas
¥Poor oxygenationÑincrease FiO2, optimize PEEP, increase inspiratory pressure or tidal volume(Vt) if chest rise is not adequate, increase inspiratory time(Ti), and try inverse ratio ventilation if severe ARDS.
85 Mechanical Ventilation |
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Table 85.2 Indications for high-frequency oscillatory ventilation
Requiring mean airway pressure more than 20
Not maintaining saturations with PEEP more than 14, FiO2 more than 0.6
Oxygenation index more than 16 (oxygenation index = mean airway pressure × FiO2 × 100/PaO2)
Consider early use rather than as a rescue therapy
¥High PaCO2Ñignore if pH is acceptable (>7.2) unless there is increased intracranial pressure or severe pulmonary hypertension (permissive hypercapnia).
¥To decrease PaCO2, increase rate or increase PIP or Vt. In bronchospasm, decrease rate and increase expiratory time to prevent air trapping.
¥High PaO2Ñdecrease FiO2.
¥Low PaCO2Ñdecrease rate and decrease Vt.
Step 4: Weaning
Ventilatory settings are reduced once the primary pathology or condition that led to ventilation is improving. There are no set protocols for weaning. Different protocols are followed by different institutions. Generally, the following pattern is adopted:
¥FiO2 is weaned Þrst to 0.4, maintaining saturation in acceptable range.
¥Mode is changed to Synchronized intermittent mandatory ventilation (SIMV) with pressure support mode or pressure support mode.
¥PEEP is decreased gradually in steps of 2 cm H2O to 4Ð5 cm H2O.
¥SIMV rate is decreased to 5Ð10.
¥The patient is reassessed after each change in the settings, and if the oxygen requirement goes up or the patient develops respiratory distress or is hypercarbic on blood gas, weaning process is paused and the support level is increased.
Some patients (especially when the lung is normal or short ventilation for neuro-
logical indications) can be directly given a spontaneous breathing trial after stopping sedation and extubated without weaning.
Step 5: Spontaneous breathing trial
¥Spontaneous breathing trial is done before extubation to assess extubation readiness. It can be done with a T piece after disconnecting ventilator, endotracheal continuous positive airway pressure (CPAP), or minimal pressure support with CPAP.
¥Usually the pressure support (PS) level is adjusted to the size of endotracheal
tube (ETT) (6 cm H2O PS for ETT >5 mm, 8 cm for ETT 4Ð5 mm, and 10 cm for ETT 3Ð4 mm).
Duration of the trial ranges from 30 min to 2 h. The following are the criteria for
terminating a spontaneous breathing trial.
¥Inability to maintain gas exchange (needing more than 0.5 FiO2 for saturations greater than 95%)
¥Inability to maintain effective ventilation (measured exhaled tidal volume <5 mL/ kg; PaCO2 >50 mmHg or increase >10 mmHg above baseline)