A Markov computer simulation model of the economics of neuromuscular blockade in patients with acute respiratory distress syndrome.
BACKGROUND
Management of acute respiratory distress syndrome (ARDS) in the intensive care unit (ICU) is clinically challenging and costly. Neuromuscular blocking agents may facilitate mechanical ventilation and improve oxygenation, but may result in prolonged recovery of neuromuscular function and acute quadriplegic myopathy syndrome (AQMS). The goal of this study was to address a hypothetical question via computer modeling: Would a reduction in intubation time of 6 hours and/or a reduction in the incidence of AQMS from 25% to 21%, provide enough benefit to justify a drug with an additional expenditure of $267 (the difference in acquisition cost between a generic and brand name neuromuscular blocker)?


METHODS
The base case was a 55 year-old man in the ICU with ARDS who receives neuromuscular blockade for 3.5 days. A Markov model was designed with hypothetical patients in 1 of 6 mutually exclusive health states: ICU-intubated, ICU-extubated, hospital ward, long-term care, home, or death, over a period of 6 months. The net monetary benefit was computed.


RESULTS
Our computer simulation modeling predicted the mean cost for ARDS patients receiving standard care for 6 months to be $62,238 (5%-95% percentiles $42,259-$83,766), with an overall 6-month mortality of 39%. Assuming a ceiling ratio of $35,000, even if a drug (that cost $267 more) hypothetically reduced AQMS from 25% to 21% and decreased intubation time by 6 hours, the net monetary benefit would only equal $137.


CONCLUSIONS
ARDS patients receiving a neuromuscular blocker have a high mortality, and unpredictable outcome, which results in large variability in costs per case. If a patient dies, there is no benefit to any drug that reduces ventilation time or AQMS incidence. A prospective, randomized pharmacoeconomic study of neuromuscular blockers in the ICU to asses AQMS or intubation times is impractical because of the highly variable clinical course of patients with ARDS.
Macario
Alex
A
Department of Anesthesia, Stanford University School of Medicine, Stanford, CA 94305, USA. amaca@stanford.edu
Chow
John L
JL
Dexter
Franklin
F
D003198:Computer Simulation; D003362:Cost-Benefit Analysis; D016527:Drug Costs; D006699:Home Care Services / Q000191:economics; D006801:Humans; D007362:Intensive Care Units / Q000191:economics*; D007442:Intubation, Intratracheal / Q000191:economics / Q000706:statistics & numerical data; D008134:Long-Term Care / Q000191:economics; D008297:Male; D008390:Markov Chains; D008875:Middle Aged; D009135:Muscular Diseases / Q000139:chemically induced; D019148:Neuromuscular Blockade / Q000009:adverse effects / Q000191:economics*; D009466:Neuromuscular Blocking Agents / Q000009:adverse effects / Q000191:economics* / Q000627:therapeutic use; D011782:Quadriplegia / Q000139:chemically induced; D019057:Quality-Adjusted Life Years; D012121:Respiration, Artificial / Q000191:economics / Q000706:statistics & numerical data; D012128:Respiratory Distress Syndrome / Q000191:economics* / Q000628:therapy; D013577:Syndrome
D009466:Neuromuscular Blocking Agents