Conditions: Acute Lung Injury
Keywords: Acute Lung Injury Extravascular Lung Water Acute Respiratory Distress Syndrome
Allocation: RANDOMIZED | Intervention model: PARALLEL
Enrollment: 33
Healthy volunteers: no

Brief summary:
The purpose of this study is to test a treatment that tries to reduce the amount of fluid in the lungs of subjects with acute lung injury to see if this is helpful.

Detailed description:
The objective of this study is to conduct a randomized, controlled trial of a goal directed therapy designed to improve outcome in patients with acute lung injury (ALI). The investigators are comparing two algorithmic approaches in managing patients with ALI - one, the control arm, attempts to reduce the amount of fluid in the lung in patients with ALI by diuresis based on central venous pressure and urine output, the other the treatment arm attempting to reduce lung water by directing therapy to measured lung water and using more sensitive indicators of preload status than CVP. The protocol uses measured extravascular lung water (EVLW) to direct diuresis and appropriate fluid restriction in a goal directed fashion in order to lower EVLW towards the normal range.

Arms:
arm 1: The investigators control arm consists of a simplified algorithm for conservative management of fluids in patients with ALI, as to be published by the ARDSnet group, based on the protocol used in the FACTT trial. The protocol calls for strict adherence to ARDSnet ventilation, our weaning protocol and use of only select vasoactive, beta-adrenergic drugs as it is felt that variation in these treatments could seriously confound our results. Albuterol administration will not be permitted in the either arm except for life threatening bronchospasm not responsive to ipratropium. Ipratropium may be administered at the treating physician's discretion for bronchospasm. PiCCO's will be placed in each control patient and data recorded twice daily. The treating physician's will be blinded to this data. arm 2: When EVLW exceeds 9 ml/kg PBW the algorithmic treatment is begun and continued until EVLW ≤9 ml/kg PBW or extubation whichever comes first as tolerated (see figure 6). Furosemide and volume contraction are initiated when sufficient volumetric preload (GEDI) is available to enact volume contraction as a means to decrease measured EVLW without causing concomitant hypoperfusion. Fluid administration is also guided by changes in EVLW. An increase in EVLW \> 2ml/kg PBW as a result of fluid administration curtails any further fluid administration until the next scheduled measurement.

Our ultimate treatment goal is to maximally lower EVLW towards the normal range - thus improving lung mechanics and gas exchange - without causing concomitant hemodynamic compromise and end-organ injury. By doing so we feel this algorithmic, goal directed, therapeutic approach should improve outcome.

Interventions: intervention 1: Diuresis (furosemide) part I intervention 2: Fluid Bolus (crystalloid or albumin) intervention 3: Fluid Bolus (crystalloid or albumin) intervention 4: Vasopressors (Norepinephrine, Vasopressin, Phenylephrine, Epinephrine) intervention 5: Vasopressors (Norepinephrine, Vasopressin, Phenylephrine, Epinephrine) intervention 6: Dobutamine intervention 7: Dobutamine intervention 8: Concentrate all drips and nutrition intervention 9: Diuresis (furosemide) part II intervention 10: Dialysis
Intervention descriptions: intervention 1: Goal: Overall I/O net negative 50ml/hour

Initiation:

1. Continuous IV furosemide at 3mg/hour or last known protocol specified dose
2. Titrate up or down by 3mg/hour increments every hour as needed to establish diuresis goal
3. Do not exceed 30mg/hour

Furosemide Bolus:

1. If unable to establish adequate diuresis at maximum dose may attempt furosemide bolusing as follows
2. By intravenous bolus give 30, then 60, then 80, and 120 mg - one bolus dose every hour until urine output results in 1 ml/kg PBW/hr net negative fluid balance per hour
3. Bolusing trials may be done at will but total furosemide dose may not exceed 800mg/24hour period intervention 2: 15 ml/kg PBW crystalloid (round to nearest 250 ml) or 25 grams albumin as rapidly as possible. Used for patients with a measured CVP\<8 or measured PaOP \<12mmHg in addition to concurrent urine output of \<0.5 ml/kg/hr intervention 3: 10 ml/kg PBW crystalloid (round to nearest 70ml) or 25 grams albumin as rapidly as possible.

Perform thermodilution immediately before and after and 60 minutes after each bolus. If EVLW increases \> 2ml/kg PBW within 60 minutes after a bolus do not give any further boluses until next regularly scheduled measurement. This therapy is available for patients with a map \< 60 or who are on vasopressors that also have a measured GEDI less than goal intervention 4: (may use any alone or in combination)

1. Norepinephrine - 0.05mcg/kg/min - increase for effect not to exceed (NTE) 1mcg/kg/min.
2. Vasopressin - 0.04 international units/hour
3. Phenylephrine - 7mcg/min - may increase to for effect not to exceed 500mcg/min.
4. Epinephrine - 1 mcg/min - may increase for effect not to exceed 20mcg/min.

Weaning: When MAP ≥ 60 mm/Hg on stable dose of vasopressor begin reduction of vasopressor by greater than or equal to 25% stabilizing dose at intervals ≤ 4 hours to maintain MAP ≥ 60 mm/Hg. intervention 5: (may use alone or in combination)

1. Norepinephrine - 0.05mcg/kg/min - increase for effect not to exceed (NTE) 1mcg/kg/min.
2. Vasopressin - 0.04 international units/hour
3. Phenylephrine - 7mcg/min - may increase to for effect not to exceed 500mcg/min.
4. Epinephrine - 1 mcg/min - may increase for effect not to exceed 20mcg/min.

Weaning: When MAP ≥ 60 mm/Hg on stable dose of vasopressor begin reduction of vasopressor by greater than or equal to 25% stabilizing dose at intervals ≤ 4 hours to maintain MAP ≥ 60 mm/Hg.

In the experimental arm vasopressors are a treatment option in patients with a Mean Arterial Pressure of \< 60 intervention 6: 1. Begin at 5mcg/kg/min and increase by 3 mcg/kg/min increments at 15 minute intervals until C.I. ≥ 2.5 or maximum dose of 20mcg/kg/min has been reached.
2. Begin weaning 4 hours after low CI is reversed. Wean by ≥ 25% of the stabilizing dose at intervals of ≤ 4 hours to maintain hemodynamic algorithm goals.
3. If patient is on dobutamine as a result of an earlier cell assignment, dobutamine should be ignored for the purpose of subsequent assignment, but should be continued to be weaned per protocol.

Used in patients with a measured cardiac index \< 2.5 intervention 7: 1. Begin at 5mcg/kg/min and increase by 3 mcg/kg/min increments at 15 minute intervals until C.I. ≥ 2.5 or maximum dose of 20mcg/kg/min has been reached.
2. Begin weaning 4 hours after low CI is reversed. Wean by ≥ 25% of the stabilizing dose at intervals of ≤ 4 hours to maintain hemodynamic algorithm goals.
3. If patient is on dobutamine as a result of an earlier cell assignment, dobutamine should be ignored for the purpose of subsequent assignment, but should be continued to be weaned per protocol. intervention 8: Concentrate all drips and nutrition in order to minimize fluid volume as much as possible. Intravenous fluid to be run at keep vein open rate.

EVLW arm: Patients with a MAP \> 60 and off vasopressors for \>12 hours, as well as patients with a measured cardiac index \>2.5 that also have a measured GEDI \> goal. intervention 9: Withhold furosemide if:

1. Significant hypokalemia (K+ \<= 2.5 meq/L), or hypernatremia (Na+ \>= 155 meq/L) occurs within last 12 hours may then be restarted if the prevailing condition no longer exists
2. Dialysis dependence
3. Oliguria (less than 0.5ml/kg/hour) with either creatinine \> 3, or clinical suspicion of rapidly evolving ARF
4. More than 800mg has been given in less then 24 hours
5. Creatinine increases \> 1.5 mg/dl in any 24 hour period intervention 10: 1. Need for CVVHD or intermittent hemodialysis to be determined by treating clinicians.
2. CVC arm: If fluid management to be accomplished with dialysis then fluid balance goals to be determined per clinicians.
3. EVLW arm: Fluid balance as per algorithm
4. When using intermittent HD it is recommended that no more than 2 liters net negative fluid is removed per dialysis session. Total fluid removal per run to be estimated by the clinicians to attain CVP or GEDI goals per algorithm.

Protocol document: