ICU Flashcards
Options for management of gas trapping (aka AutoPeep)
Decrease RR
Decrease TV
Increase expiration time in I:E ratio
Differentiate septic from cardiogenic shock based on Central venous gas
CVO2 >80% = sepsis/high flow
CVO2 <60% = cardiogenic
qSOFA
-define sepsis and septic shock
Sepsis: 2/3 of:
1) RR>=22
2) SBP <=100
3) Altered LOC (GCS<15)
Septic shock: lactate >2mmol/L and requiring pressors for MAP>65
Dynamic Measures of Fluid responsiveness
Fluid challenge (500cc): Increases SV by 10-15% or increased pulse pressure by 15%
Passive leg raise (inc BP by 10-15%)
Lactate
Cap refill: press glass slide on finger until white for 10s if time to normal color <3s = NORMAL
IVC Distendability index
- NOT intubated: >40% IVC collapse with inspiration
- Intubated & ventilated on controlled mode: >15-20% distension with expiration
- Intubated breathing spontaneously - CANNOT Use
Hemodynamic Effect: Norepinephrine and Dopamine
Norepi: ++ SVR, + HR, +/nil CO, + PCWP (all up)
Dopamine: + SVR, + HR, + CO, + PCWP
(all up; same as norepi but higher risk tachy)
Hemodynamic Effect: Epinephrine
+ SVR, ++ HR, + CO, - PCWP
same as norepi except PCWP drops; higher risk tachy
Hemodynamic Effect: Vasopressin
+ SVR, nil HR, nil CO, + PCWP
*S/E: digit/gut ischemia bc peripheral vasoconstrict
Hemodynamic Effect: Phenylephrine
+ SVR, - HR, - CO, + PCWP
(opposite dobutamine; similar to vaso but drops HR and CO - reflex brady)
*use in opioid induced hypotension
Hemodynamic Effect: Dobutamine/Milrinone
- SVR, + HR (Dob>Milrinone), + CO, - PCWP
* Milrinone long halflife, not for renal failure
Indications for corticosteroids in septic shock
MAP <65 despite fluids and norepi or epi >0.25mcg/kg/min x4h (dose = 200 mg/day hydrocortisone or 50mg q6h)
Norepinephrine dose range
0.03-0.35 mcg/kg/min
Strategies to improve ventilation in intubated hypoxic resp failure:
- Increase FiO2
- Increase PEEP
- Sedate and Paralyze
- Prone or roll on good lung down to increase VQ mismatch
- Inhaled NO
- ECMO
Strategies to improve ventilation in hypercarbic resp failure:
- Increase RR
- Increase TV
- Increase I:E ratio
4 Types of Respiratory Failure
1) Hypoxic (PaO2 <60)
2) Hypercapenic (PaCO2 >45)
3) Post-op - due to atelectasis, dec FRC
4) Circulatory collapse
Indications for NIPPV
1) Mild-Severe hypercapneic COPD (RR 20-40, pCO2 >45, pH<= 7.35) if LOC not significantly altered
2) Cardiogenic pulmonary edema
3) Avoid intubation: IC, post-op (GI/pelvic, supra-diaphragm sx) with resp failure, high risk post-extubation pt (Age >=65, resp/CV comorbidity)
Contraindications to NIPPV
1) Altered LOC - unable to protect airway
2) Inability to clear secretions
3) Hemodynamically unstable (reduces preload)
4) Facial fractures/ surgery/ obstruction
5) Indication for intubation, failed extubation
Definition ARDS
1) Acute resp failure (PF ratio <300 on PEEP 5) +
2) Developed within 1 week of acute insult (local - PNA, aspiration, contusion; systemic - sepsis, pancreatitis, drug ingestion, TRALI)
3) Bilateral airspace opacities on CXR not fully explained by cardiogenic pulmonary edema, effusions, lobar/lung collapse or nodules
Severity of ARDS
PF 200-300 = Mild
PF 100-200 = Moderate
PF <100 = severe
*PaO2/FiO2
Treatment strategies ARDS
1) Lung protective vent: Vt 4-8 cc/kg, P plat <30, PIP <40
- Keep RR <35 and PaCO2<25 to target pH 7.3-7.45
- I:E ratio 1:1 - 1:3
2) High PEEP (if FiO2 >=50%) - Target SpO2 88-95%, PaO2 55-80,
3) Prone (>12hr/day) - mort benefit when PF ratio <150
4) Sedation/Paralysis if:
- PF <150
- Vent asynchrony
- Not for mild or mod/severe on lung protective vent w/ light sedation
- Unclear mortality benefit: Recruitment maneuvers, ECMO, diuresis
- *No mortality benefit: Statin, steroids, inhaled NO (may improve oxygenation)
- **HARM: DO NOT do high-frequency oscillation
Risks and Benefits High PEEP Strategy
Benefits:
- Increase alveolar recruitment
- Decrease lung strain
- Decrease atelectrauma
Risks:
- Overdistension –> dead space
- Increase pulmonary vascular resistance and intrapulmonary shunt
Criteria for extubation
- Underlying cause for intubation resolved
- PF ratio >150 or SpO2 >90% on FiO2<=40% and PEEP of <=5
- pH >7.25
- Adequate CV status (on minimal pressors)
- Adequate mentation/LOC
SBT Steps
Screen w/ rapid shallow breathing test: RR/Vt 100-105 is a pass; >105 predictive of failed extubation
Reduce inspiratory/expiratory assistance for 30-120 min and see if patient can tolerate (desat, RR, distress, vitals). If ok, passed!
Weaning Methods:
1) Reduce pressure support during PSV/PEEP (eg 0 on 0) for 30 min OR
2) CPAP OR
3) T piece
Treatment ICU Delirium
Non-pharm = 1st line
Pharm:
- Analgesia (opioids) > Antipsychotics (Atyp >Typ) > Sedatives (Benzos) = HARM
- IV Bolus > Infusion
- Consider dexmedetomidine (S/E: brady/hypotension) to help facilitate extubation in ICU delirium
ICU Sedation target
RASS -2 to +1
-2 = moderate sedation, but moves and opens eyes
+1 = anxious but not aggressive or agitated
ICU Sedation: Preferred agents
Propofol
Opioids
Dexmedetomidine
NO BENZOS
Definition Brain Death
Irreversible cessation of brain and brainstem function
Definition Persistent Vegetative State
Severe anoxic brain injury –> wakefulness without awareness or purposeful response
Sleep wake cycles intact
Definition Minimally Conscious State
Awake with limited interaction
Follows basic commands and/or vocalizes
Neurologic Determination of Death (NDD) Criteria
- Agreed by 2 MDs
- Injury compatible with NDD
- 24hs after inciting event eg cardiac arest
- No brainstem reflexes: pupil, gag, cough, corneal, oculovestibular (no response to caloric testing)
- No movement: spontaneous or response to noxious stim (B/L and above/below clavicles; EXCLUDES spinal relexes)
6 Positive apnea testing: pCO2 >60 AND >20 above pre-apnea baseline AND pH <=7.28 once disconnected from vent - No confounding factors: shock, hypothermia <34C, metabolic abn (PO4<0.4, Ca<1, Mg<0.8, Na>160 or <125, Gluc <4), neuromuscular blockade, interfering drugs, Nerve/Muscle dysfcn (GBS, botulism, MG) , hypoxic ischemic encephalopathy
* if confounding factors: ancillary testing to show absent cerebral blood flow via radionuclide/CT/MR/ 4 vessel angiography (CANNOT use EEG)
Donation after Cardiocirculatory Death (Controlled) Criteria
- Non-recoverable illness with dependence on life support and intention to withdraw with imminent death once withdrawn
- More than 24 hours from inciting event
- Maximum time from withdrawal of life support to death is 1-2 hours (depending on organ)
JAMA: Will this patient be difficult to intubate?
+ LR:
Best = Grd 3 upper lip bite test (lower incisor can’t reach top lip)
Hyomental distance <3 cm
Retrognathia (mandible <9cm from angle jaw to tip chin)
Malampati >=3
Stages of Hypothermia and their treatment
HT1: T32-35, conscious and shivering
- Passive rewarming (warm enviro/clothes), + mvment
HT2: T28-32, imp LOC, no shivering, VSS
- Cardiac monitors, active external warming (warm blanket, bear-hugger), warmed IV fluids, avoid mvment (to avoid arhythmias)
HT3: T24-28, unconscious, VS abn but present
- Same warming as HT2, external + warmed IV fluids, avoid mvement
- Airway management + ECMO/Bypass if cardiac instability
HT4: T<24, no vitals
- CPR w/ epi and defib, with active external and INTERNAL rewarming
Shock differential
Hypovolemic: hemorrhage, pancreatitis
Obstructive: PE, tamponade, tension PTX
Cardiogenic: ACS, arrhythmia, valvulopathy, HF
Distributive: septic, anaphylaxis, SIRS, pancreatitis, mitochondrial dysfcn (eg cyanide), endocrine (thyroid, adrenal crisis), HLH, meds, liver failure, neurogenic shock
SIRS
2/4: WBC>12, <4, or >10% bands T>38 or <36 HR>90 RR>20 or PCO2<32
Tx for sepsis/septic shock
Initial:
Measure lactate and repeat in 2-4h if >2mmol/L
Cultures + abx w/i 1h if shock/unclear (otherwise can delay up to 3h)
Fluids at least 30ml/kg w/i first 3h
Vasopressors to keep MAP >65
Later:
Steroids if MAP<65 despite fluid and 1 pressor x4h
Transfuse if Hgb <70 , consider if hypoxic, hemorrhage, acute MI
VTE ppx (LMWH>UFH)
Stress ulcer ppx (lansoprazole 30 or Panto 40) if coagulopathic, liver dz, shock, or intubated
BG target 8-10 (Insulin if BG>10)
Bicarb if pH<7.2 AND AKI
Feed within 72h if no escalating pressor reqment
*Do NOT give: immunoglobulins, polymyxin, Vit C, activated prot C, angiotensin ii, O2>96%
Reasons to use NS over RL
Refractory hyperK
TBI
Hx of mitochondrial disease
Adrenergic receptors
Alpha 1: increase SVR
Alpha 2: Decrease SVR (eg clonidine)
Beta 1: Inotropy, chronotropy, domotrophy (conduction)
Beta 2: bronchodilation, relax smooth muscles, gallbladder, uterus
HFNC benefits
- Heated/humidified gas –> increased secretion clearance and less bronchoconstriction
- Washout CO2 decreased dead space
- High nasal inspiratory flow (up to 60L/min) decreases upper air resistance
- Positive airway pressure recruits leads to recruitment of atelectasis (gives minimal PEEP)
- Decreased entrainment ambient air increases FiO2
When to use / not use HFNC:
Use:
- Type 1 Resp failure
- NIVV breaks
- Low/mod risk extubation failure non-surgical patients
- HFNC or conventional O2 in post-op patients at low risk of respiratory complications; if high risk (HFNC or NIV)
Not use:
- High risk extubation failure patients
- Acute hypercapneic resp failure secondary to COPD - trial NIV before HFNC
CPAP vs BIPAP
CPAP improves oxygenation
BiPAP improves oxygenation when you increase EPAP and ventilation when you increase IPAP
Refractory hypoxia on vent
- Optimize lungs: diurese, no new PNA
- Optimize PEEP, electric impedance tomogaphy, esophageal balloon
- Offload lungs (NG to decompression stomach, elevate HOB)
- Sedate
- Prone if PF<150
- Neuromuscular blockade if mod/severe and cannot achieve lung protective vent (eg hypoxic, vented prone, dysynchronous/high plat P)
COVID therapies
1) Dex 6mg PO/IV x10d (if req O2, hospitalized, intubated; NOT for outpatients) - reduced mort and need for MV
2) Remdesivir 200mg IVx1 then 100mg IVx4d (if need O2 but NOT intubated)
3) Tocilizumab (if need O2/intubation, with CRP>75 and wosening despite 1-2d steroids) - reduced mort
4) Casirivimab + imdevimab and sotrovimab - specific cases
5) VTE prevention
Not recommended: empiric abx, colchicine, IFN, vit D, Plaquenil, Ivermectin, Lopinavir, ritonavir
Findings of Migrated ETT, PTX, Collapse/Plug
ETT migrated to R: trachea displaced to left w/ decreased air entry and percussion on left
PTX: trachea away from affected w/ decreased air entry and percussion on affected
Collapse: trace towards affected w/ decreased air entry and percussion on affected side
Gas Trapping causes
ETT: kinked, clogged by sputum, patient biting on ETT –> suction or fix
Vent: high RR, high I:E ratio –> lower RR or lengthen I:E ratio (1:4/5) or decrease VT
Patient: high RR, bronchospasm –> bronchodilate
Last line tx: disconnect vent and press on chest, Heliox, high freq oscillation, extracorporeal carbon dioxide removal
Critical illness myopathy vs critical illness polyneuropathy vs glucocorticoid induced myopathy
Motor: affected in all 3, flaccid quadriparesis + failue to wean in CIM and CIP
Sensory affected in CIP, but spared in CIM and GIM
Reflexes: normal/low in CIM, low in CIP, nomal GIM
CIM: CK up, dx w/ EMG and NCS, no tx
CIP: sepsis is RF
GIM: cushing like syndrome, dx by reducing steroid dose and monitor sx
Highest LR+ for neuroprognostication (poor outcome)
No N20 somatosensory evoked potential cortical wave 24-72h after cardiac arrest or rewarming
M1/M2 motor score at 72hr+
ETCO2 monitoring during CPR target
10mmHg
Pregnant ACLS
Left lateral uterine displacement >20wks
IV above diaphragm
Stop CaCl or Ca gluc if giving IV Mg
Consider postmortem cesarean delivery at 5min of resuscitation
Targeted Temp Management after ROSC
24 hours at 33-36C, consider 36 if arrhythmia or CV instability
