MDCalc » Critical Care

King’s College Criteria

admin — Thu, 18 Mar 2010 11:53:44 +0000

Fulminant hepatic failure secondary to acetaminophen poisoning: a systematic review and meta-analysis of prognostic criteria determining the need for liver transplantation. Crit Care Med. 2003 Jan;31(1):299-305.
Goldfrank's Toxicologic Emergencies, 8th Edition.
Treatment of hepatic encephalopathy. N Engl J Med. 1997 Aug 14;337(7):473-9.

Grade 1 - Inverted sleep pattern; forgetfulness, mild confusion, agitation, irritability, tremor, apraxia
Grade 2 - Lethargy, slow responses; Disorientation for time or place, Subtle personality change; Asterixis, dysarthria, ataxia
Grade 3 - Somnolence but rousability, Disorientation as regards place; Asterixis, hyperactive reflexes, Babinski signs, muscle rigidity
Grade 4 - Coma (unresponsive to verbal or noxious stimuli)

Glasgow-Blatchford Bleeding Score (GBS)

admin — Thu, 08 Oct 2009 03:34:18 +0000

Glasgow-Blatchford Score

Blood Urea
≥6·5 <8·0	2
≥8·0 <10·0	3
≥10·0 <25·0	4
≥25	6
Hemoglobin (g/L) for men
≥12.0 <13.0	1
≥10.0 <12.0	3
<10.0	6
Hemoglobin (g/L) for women
≥10.0 <12.0	1
<10.0	6
Systolic blood pressure (mm Hg)
100–109	1
90–99	2
<90	3
Pulse ≥100 (per min)	1
Presentation with melaena	1
Presentation with syncope	2
Hepatic disease	2
Cardiac failure	2

Low risk = Score of 0. Any score higher than 0 is "high risk" for needing a medical intervention of transfusion, endoscopy, or surgery.

A risk score to predict need for treatment for uppergastrointestinal haemorrhage. Lancet 2000.

A risk score to predict need for treatment for uppergastrointestinal haemorrhage. The Lancet, 2000.

A risk score to predict need for treatment for uppergastrointestinal haemorrhage. Am J Emerg Med. 2007.

Outpatient management of patients with low-risk upper-gastrointestinal haemorrhage: multicentre validation and prospective evaluation. The Lancet, 2009.

Sodium Correction Rate in Hyponatremia

admin — Mon, 05 Oct 2009 22:34:19 +0000

Change in Serum Sodium = (Fluid Sodium - Serum Sodium) / (Total Body Water + 1)

Total Body Water = (Wt in kg * % Water)

Age	Male	Female
Child	0.6	0.6
Adult	0.6	0.5
Elderly	0.5	0.45

*Experts recommend correcting no faster than 12 mmol/L/day (0.5mmol/L/hr) to avoid central pontine myelinolysis (first calculation), and only correcting it faster — and only using hypertonic (3%) saline — if the patient is seriously symptomatic at a rate of 1-2 mmol/L/hr (second/third calculations), and even then, only correcting it at 1-2 mmol/L/hr for <3 hours.

Hyponatremia. Adrogué HJ, Madias NE. NEJM, 2000.

PERC Rule for Pulmonary Embolism

admin — Wed, 11 Feb 2009 14:42:47 +0000

Phenytoin/Dilantin Correction for Albumin or Renal Failure

admin — Tue, 10 Feb 2009 14:56:28 +0000

The Sheiner-Tozer Equation is Used for an Accurate Estimate:
Corrected Phenytoin = Measured Phenytoin Level / ( (adjustment x albumin) + 0.1)

Adjustment = 0.2; In patients with Creatinine Clearance < 20, adjustment = 0.1.

Martin E, Tozer TN, Sheiner LB, Riegelman S. The clinical pharmacokinetics of phenytoin. J Pharmacokinet Biopharm. 1977 Dec;5(6):579-96.

CURB-65 Severity Score for Community-Acquired Pneumonia

admin — Tue, 10 Feb 2009 13:16:18 +0000

Lim WS, Lewis S, Macfarlane JT. Severity prediction rules in community acquired pneumonia: a validation study. Thorax. 2000 Mar;55(3):219-23.

Winters’ Formula for Metabolic Acidosis Compensation

admin — Fri, 02 Jan 2009 04:36:19 +0000

Expected pCO₂ = 1.5 * HCO₃^- + 8 +/- 2

Well’s Criteria for Pulmonary Embolism / PE

admin — Fri, 02 Jan 2009 04:35:11 +0000

Derivation of a simple clinical model to categorize patients probability of pulmonary embolism: increasing the models utility with the SimpliRED D-dimer. Thromb Haemost. 2000 Mar;83(3):416-20.

Sodium Deficit in Hyponatremia

admin — Fri, 02 Jan 2009 04:28:13 +0000

Sodium Deficit = Total Body Water * Normal Wt in kg * (Desired Na - Pt's Na) (TBW = 0.6 if male and 0.5 if female)

Remember not to correct too rapidly to avoid central pontine myelinolysis!

San Francisco Syncope Rule to Predict Serious Outcomes

admin — Fri, 02 Jan 2009 04:27:13 +0000

Note: This rule has a 96% sensitivity and 62% specificity for serious outcome. Negative predictive value: 99.2%; positive predictive value 24.8%.

Serious Outcome in this study is defined as "death, myocardial infarction, arrhythmia, pulmonary embolism, stroke, subarachnoid hemorrhage, significant hemorrhage, or any condition causing a return ED visit and hospitalization for a related event."

The San Francisco Syncope Rule to Predict Patients with Serious Outcomes

Lactate > 3.5 mg/dL (0.39 mmol/L) 4 hrs after early fluid resuscitation?	Yes
pH < 7.30 or lactate > 3 mg/dL (0.33 mmol/L) after full fluid resuscitation at 12 hours	Yes
INR > 6.5 (PTT > 100s)	Yes
Creatinine > 3.4 mg/dL (300 µmol/L)	Yes
Grade 3 or 4 Hepatic Encephalopathy?	Yes
Phosphorus > 3.75 mg/dL (1.2 mmol/L) at 48 hours	Yes

Is patient female?	Yes
Hemoglobin	g/dL
BUN	mg/dL
Initial Systolic Blood Pressure	mm Hg
Heart Rate ≥ 100	Yes
Does the patient have melena?	Yes
Did the patient have syncope?	Yes
Does the patient have hepatic disease?	Yes
Does the patient have heart failure?	Yes
Score	points

Is patient female?	Yes
Age	Child Adult Elderly
Normal Pt Weight	lbs
Serum Na	mmol/L
Type of Fluid	3% Saline (513 Na mmol/L) Normal Saline (154 Na mmol/L) Ringer's Lactate (130 Na mmol/L) 1/2 Normal Saline (77 Na mmol/L)
Fluid Rate to Increase Sodium by 0.5 mmol/L/hr	ml/hr of selected fluid
Fluid Rate to Increase Sodium by 1 mmol/L/hr*	ml/hr of selected fluid
Fluid Rate to Increase Sodium by 2 mmol/L/hr*	ml/hr of selected fluid

Age < 50?	Yes
HR < 100?	Yes
O2 Sat on Room Air >94%?	Yes
No Prior History of DVT/PE?	Yes
No Recent Trauma or Surgery?	Yes
No Hemoptysis?	Yes
No Exogenous Estrogen?	Yes
No Clinical Signs Suggesting DVT?	Yes
Score	points

Patient's calculated Creatinine Clearance < 20?	Yes
Phenytoin Level	mg/L
Serum Albumin	g/dL
Corrected Phenytoin	mg/L

Confusion?	Yes +1
BUN > 19 mg/dL (7 mmol/L)?	Yes +1
Respiratory Rate ≥ 30?	Yes +1
Systolic BP < 90 mmHg or Diastolic BP ≤ 60 mmHg?	Yes +1
Age ≥ 65?	Yes +1
Score

ABG's Calculated HCO₃^-	mEq/L
Expected pCO₂ Compensation	mmHg

Clinical Signs and Symptoms of DVT?	Yes +3
PE Is #1 Diagnosis, or Equally Likely	Yes +3
Heart Rate > 100?	Yes +1.5
Immobilization at least 3 days, or Surgery in the Previous 4 weeks	Yes +1.5
Previous, objectively diagnosed PE or DVT?	Yes +1.5
Hemoptysis?	Yes +1
Malignancy w/ Treatment within 6 mo, or palliative?	Yes +1
Score

Congestive Heart Failure history?	Yes +1
Hematocrit < 30%?	Yes +1
ECG Abnormal ?	Yes +1
Shortness of Breath History?	Yes +1
Systolic BP < 90 mmHg at Triage?	Yes +1
Score	points