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Coexisting Disease · 18 min

Coexisting disease — last-night quick guide

12 most-tested coexisting conditions: induction strategy, what NOT to give, what to monitor, when to delay.

Watch out

Coexisting disease = 30% of NCE

Stoelting + Hines is the canonical text. Don't memorize one-off facts — memorize the perioperative-management pattern per disease.

Rule

Ischemic heart disease

Goal: maintain MYOCARDIAL O₂ SUPPLY > DEMAND. Avoid tachycardia, hypotension, hypoxia, anemia. Continue beta-blockers + statins (DECREASE/POISE-2). Stop ACEi/ARB morning of surgery. DAPT: bare-metal stent ≥30 days · drug-eluting ≥6 months. Monitor: 5-lead ECG, art line, TEE if pump function poor.

Rule

Severe aortic stenosis

Fixed obstruction. Preload-, rate-, and sinus-rhythm-dependent. AVOID tachycardia, hypotension, AFib (loss of atrial kick = ↓ CO 30%). Phenylephrine first-line (no tachycardia, raises SVR + coronary perfusion). Spinal generally CONTRAINDICATED in severe AS.

Rule

COPD

Smoking cessation ≥8 weeks ideal. Continue inhalers AM of surgery. ARISCAT for risk. Intraop: longer expiratory time, permissive hypercapnia, sevo bronchodilation, AVOID atracurium + morphine. Regional preferred when feasible.

Rule

OSA / STOP-BANG ≥3

Anticipate difficult MV + intubation + post-op resp depression. Ramp position. Continue CPAP. MINIMIZE OPIOIDS — multimodal (acetaminophen + ketorolac + regional + ketamine ≤0.5 mg/kg/hr + dex). AVOID benzos. Reverse NMB fully (TOF >0.9). Extended PACU.

Rule

Diabetes

Hold metformin morning of surgery. SGLT2 inhibitors hold ≥3-4 days pre-op (DKA). T1DM: ½ long-acting AM + rapid-acting prn. Goal intraop 140-180 (NICE-SUGAR). Diabetic gastroparesis = full-stomach precautions.

Rule

ESRD on hemodialysis

Dialyze ≤24 h pre-op. Confirm K+. AVOID succinylcholine (each dose ↑K 0.5-1 mEq/L). Use cisatracurium or rocuronium-with-sugammadex. Avoid morphine (M6G accumulates), pethidine. AV-fistula arm: NO BP cuff, NO IV, NO art line on that side.

Rule

Cirrhosis (Child-Pugh / MELD)

↓ albumin → more free drug; ↓ pseudocholinesterase → prolonged sux + ester locals. Avoid hepatically-cleared drugs at high dose. Cisatracurium preferred. INR poor predictor of bleeding in cirrhosis — use TEG/ROTEM. MELD ≥15 = significant perioperative risk.

Rule

Pheochromocytoma

ALPHA blockade FIRST ≥7-14 days (phenoxybenzamine 10 mg BID titrated up). Goals: orthostatic BP, HR <80, mild nasal congestion. THEN beta-blockade only after alpha. AVOID ketamine, ephedrine, metoclopramide, droperidol, atropine. Drugs of choice: nicardipine, magnesium, phentolamine, nitroprusside.

Rule

Hyper / hypothyroidism

HYPERTHYROID elective surgery: AVOID until euthyroid. Storm: cooling + esmolol/propranolol + PTU + hydrocortisone + iodine 1 hr after PTU. AVOID ketamine + ephedrine. HYPOTHYROID severe: replace before elective; emergent + severe → IV T4 + hydrocortisone. Sensitivities: opioid + sedative.

Rule

Asthma

Continue inhalers + steroids morning of surgery. Pre-op albuterol neb 30-60 min before induction. AVOID atracurium, morphine, desflurane induction in naive. LMA > ETT when feasible. Sevo bronchodilatory. Bronchospasm: deepen → albuterol → epi → magnesium → ketamine.

Rule

OUD / buprenorphine

ASRA 2020 + Lembke 2019: CONTINUE buprenorphine through surgery. Multimodal post-op: regional, acetaminophen, NSAIDs, ketamine, dex, gabapentinoid. Full agonist opioid CAN be given on top of buprenorphine (higher dose). Methadone: continue + add full agonist; check QT.

Rule

Frailty (geriatric)

Fried/CFS frailty score predicts mortality + delirium > age alone. Reduce drug doses 25-50%. AVOID benzos + anticholinergics. Maintain MAP within 10% baseline. Aggressive normothermia. Family at induction. Restore glasses, hearing aids, dentures in PACU.

Rule

Psych meds

MAOI: AVOID meperidine + indirect sympathomimetics. SSRI/SNRI: generally continue; serotonin syndrome with methylene blue / linezolid. Lithium: continue + maintain hydration. TCAs: continue; ↑ vasopressor sensitivity. Benzodiazepine-dependent: continue (abrupt withdrawal = seizure).

Drugs to AVOID by condition

ConditionAVOIDWhy
Severe ASSpinal, ketamine, anything dropping SVRFixed-obstruction physiology
Pheo (untreated)Ketamine, ephedrine, metoclopramide, atropineCatecholamine release
ESRD on HD + ↑KSuccinylcholineΔK 0.5-1 mEq each dose
MAOIMeperidine, ephedrineSerotonin syndrome / HTN crisis
Asthma (severe)Atracurium, morphine, des inductionHistamine / airway irritation
OSALong-acting opioid, basal PCA, benzosResp depression
Cirrhosis (C-P C)Morphine, high-dose midaz, sux (prolonged)Reduced clearance / pseudocholinesterase
FrailtyBenzos, anticholinergics, polypharmacyDelirium
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