Substance Abuse - Cocaine

Cancel Case - Depending on your facility, a positive drug screen for cocaine is reason to cancel an elective surgery Positive test interpretation - Because the primary marker for cocaine can remain in the urine for 14 days after consumption, a positive test should not imply that the patient is acutely intoxicated. It should also be noted that the positive marker is not predictive of an increased risk of acute intraoperative complications. False Positives - Amoxicillin and tonic water can create false positives Intraop medications - Treated with labetolol in acute situations. Benzodiazepines or Magnesium Sulfate may reduce the cardiovascular effects of cocaine. Phenylephrine may be more effective than ephedrine to correct hypotension. Benzodiazepines and opioids are encouraged as pretreatment to avoid the intense sympathetic response sometimes seen during intubation. Abusers of cocaine require more analgesia than do nonusers. Nitrates and hydralazine will cause further increases in HR. Calcium entry-blocking agents can potentiate the toxic effects of cocaine. Reactive airway risk - when the patient is smoking cocaine Labile blood pressures - Cocaine positive patients are more likely to need pharmacological support for both hypertensive and hypotensive events during surgery Combined substance abuse - Very likely to be abusing other substances (60-90% of cocaine users do). Synergistic side effects of cocaine are present when cocaine abuse is coupled with alcohol abuse. OB: Neuraxial anesthesia - early neuraxial anesthesia should be encouraged to reduce levels of circulating catecholamines Causes placental abnormalities - specifically an increased risk of placental abruption. Crosses the placenta - Cocaine and its active metabolites readily cross the placenta Reduced uterine blood flow - Cocaine reduces uterine blood flow and increases uterine tone. Fetal growth abnormalities - Anticipate SGA and LBW infants Preeclampsia - Cocaine abuse can cause hemodynamics to mimic preeclampsia

Cocaine causes an increase in presynaptic release of catecholamines. Cocaine also blocks reuptake of norepinephrine, dopamine, and serotonin. Reduces production of nitric oxide. These affects significantly increase sympathetic tone. Side effects of cocaine: 1. Increase in BP, HR, temperature, ALT/AST, blood glucose, and cortisol 2. Reduced platelets 3. Pulmonary hypertension (reduced nitric oxide production) Acute intoxication can lead to: 1. rhabdomyolysis 2. cardiac arrest 3. ischemic or hemorrhagic stroke 4. dysrhythmias 5. Aortic dissection 6. Sudden death Chronic use of cocaine - leads to reactive airway (if smoked), cardiomyopathy, brain atrophy, renal failure Possible procoagulant - Cocaine can have a procoagulant effect in small and large vessels