01Approach to the Critical Patient/attcp71

Immediate priorities

›Initial stabilization

›Airway protection triggers

›GCS below 8

›Refractory seizure activity

›Persistent vomiting with aspiration risk

›Breathing targets

›SpO2 94% to 98%

›End-tidal CO2 monitoring if intubated

›Circulation priorities

›Cardiac monitor

›IV access x 1 to 2

›Point-of-care glucose triggers

›Any altered mental status

›Any seizure

›Any focal neurologic deficit

›Any known or suspected sulfonylurea exposure regardless of symptoms

›Decontamination timing

›Activated charcoal window within 1 to 2 hours of ingestion

›Extended window if extended-release formulation and protected airway

Bedside decision points

›Time-critical decisions

›If glucose below 4.0 mmol/L, immediate treatment before full workup

›If no IV access, IM or intranasal glucagon pathway while access obtained

›If known or suspected sulfonylurea ingestion, octreotide pathway regardless of response to dextrose

›Rebound hyperinsulinemia risk after dextrose bolus

›Dextrose monotherapy is not a definitive strategy

›If recurrent hypoglycemia despite repeated dextrose boluses, escalate to octreotide without delay

›Single normal glucose does not permit discharge

›Recurrence can occur many hours later as dextrose effect wears off while sulfonylurea remains active

›Mandatory observation period required regardless of initial response

›If pediatric single-tablet ingestion, treat as potentially lethal regardless of formulation or apparent dose

Iatrogenic harm considerations

›Routine ED interventions requiring modification in this patient

›Intubation

›Point-of-care glucose before attributing coma to another cause

›Sedative and paralytic agents do not correct hypoglycemia

›Extubation readiness requires confirmed euglycemia, not sedation clearance alone

›Sedation

›Benzodiazepines for perceived agitation can mask ongoing neuroglycopenia

›Recheck glucose before and after sedative administration in altered patients

›Fluid loading

›Dextrose-containing maintenance fluid preferred once the bolus phase is complete

›Non-dextrose resuscitation fluid for presumed sepsis or shock can delay recognition of concurrent hypoglycemia as the driver of tachycardia and altered mental status

›Oxygen

›Routine high-flow oxygen in a normoxic patient has no specific role

›Correcting oxygenation does not correct hypoglycemia and should not delay glucose check

›Vasopressors

›Isolated sulfonylurea overdose does not typically cause vasodilatory or cardiogenic shock

›Hypotension in this context should prompt reassessment for a co-ingestant before vasopressor escalation

›Mechanical circulatory support including intra-aortic balloon pump

›Essentially never indicated for isolated sulfonylurea overdose

›A request for mechanical support should prompt reconsideration of the diagnosis for a cardiotoxic co-ingestant

›Anticoagulation

›Hypoglycemia is a recognized stroke mimic

›Empiric anticoagulation for presumed TIA without confirming euglycemia risks bleeding without benefit

›Fibrinolysis

›Point-of-care glucose is mandatory before thrombolytic administration in any stroke code

›Fibrinolysis given for a hypoglycemia-induced focal deficit exposes the patient to hemorrhage risk while the correctable cause remains untreated

›Analgesia

›Acetaminophen 650 to 1000 mg PO or IV every 6 hours in adults

›Maximum 4 g per day

›Acetaminophen 15 mg/kg PO or IV every 6 hours in children

›Maximum 75 mg/kg per day or 4 g per day, whichever is lower

›Opioid analgesia only with glucose rechecked before and after administration in altered patients

›Morphine 0.05 to 0.1 mg/kg IV if needed

Consultation and coordination

›System activation

›Poison control center consultation for any confirmed or suspected ingestion

›Antidote strategy guidance

›Observation duration guidance by specific agent

›Endocrinology or toxicology consultation for refractory or recurrent hypoglycemia

›Pediatric consultation for any pediatric ingestion

›Weight-based octreotide and dextrose dosing confirmation

›Social work involvement for accidental ingestion or neglect concern

02History/hx55

Exposure characterization

›Ingestion details

›Agent and formulation

›Glyburide

›Glipizide, including extended-release

›Glimepiride

›Chlorpropamide

›Gliclazide

›Dose estimate

›Tablet count

›Strength per tablet

›Time course

›Time of ingestion

›Time to symptom onset

›Co-ingestant timing

›Access circumstances

›Own prescription

›Grandparent or household member medication

›Pill organizer or unsecured bottle

Diabetes therapy and medication context

›Medication and dosing context

›Sulfonylurea details

›Usual home dose

›Last confirmed dose time

›Renal impairment context

›Insulin co-therapy

›Type and timing

›Recent dose changes

03Physical Exam/exam43

General and neurologic

›Key exam domains

›Vital signs

›Tachycardia

›Diaphoresis

›Hypothermia in prolonged exposure

›Mental status

›Agitation

›Confusion

›Somnolence

›Coma

›Neurologic screen

›Focal deficit mimic

›Dysarthria

›Ataxia

›Seizure activity

›Autonomic signs

›Tremor

›Mydriasis

›Pallor

Hemodynamic and toxidrome findings

›Hemodynamic assessment

›Perfusion markers

›Capillary refill delay

›Cool extremities

›Blood pressure

›Usually preserved or mildly elevated early

›Hypotension suggests co-ingestant or prolonged neuroglycopenic collapse

04Differential Diagnosis/ddx42

Hypoglycemia etiologies

›Drug-induced hypoglycemia

›Sulfonylurea-related

›ICD-10 T38.3X1A for accidental exposure

›ICD-10 T38.3X2A for intentional self-harm

›Insulin excess

›ICD-10 T38.3X1A

›Low C-peptide differentiates exogenous insulin from sulfonylurea effect

›Other secretagogue or agent

›Meglitinide exposure

›Quinolone-associated hypoglycemia

›Critical illness hypoglycemia

›Sepsis related

›ICD-10 A41.9 with hypoglycemia context

›Hepatic failure related

›ICD-10 K72.90 with hypoglycemia context

›Endogenous hyperinsulinism

›Insulinoma

›ICD-10 D13.7

›Elevated insulin and C-peptide without sulfonylurea on screen

Mimics of hypoglycemia and altered mental status

›Look-alikes ranked by danger

›Stroke or TIA

›ICD-10 I63.x or G45.x

›Highest-danger mimic due to fibrinolysis exposure if glucose unchecked

›Seizure disorder

›ICD-10 G40.x

›Sedative-hypnotic or opioid intoxication

05Laboratory Tests/lt40

Core labs for severity and clearance

›Initial laboratory panel

›Confirmatory plasma glucose

›If point-of-care result inconsistent with presentation

›Basic metabolic panel

›Potassium for insulin-driven intracellular shift

›Creatinine and eGFR for drug clearance risk

›Liver panel

›AST and ALT for hepatic clearance impairment

›Venous blood gas

›If altered mental status prolonged

›If sepsis or co-ingestant acidosis suspected

Critical sample and endocrine labs

›Critical sample concept

›Indication

›Diagnostic uncertainty about cause of hypoglycemia

›Recurrent or unexplained episodes

›Tests collected during the low-glucose episode

›Insulin

›Elevated with both sulfonylurea effect and exogenous insulin

›C-peptide

›Elevated with sulfonylurea or endogenous hyperinsulinism

›Low or suppressed with exogenous insulin administration

›Proinsulin

›Elevated supports insulinoma or secretagogue effect

›Sulfonylurea screen

›Definitive confirmation of ingestion

›Send before or independent of dextrose administration since drug level is not affected by glucose therapy

06Diagnostic Tests/dt34

Scoring Systems

›Bedside diagnostic frameworks

›Whipple triad

›Symptoms consistent with hypoglycemia

›Low measured glucose at the time of symptoms

›Symptom resolution after glucose correction

›Poison Severity Score

›Mild symptoms without recurrent hypoglycemia

›Severe symptoms with coma or seizure

›Risk stratification elements

›Agent potency and duration of action

›Ingested dose relative to body weight

›Renal function

›Pediatric age

MRI

›Limited role imaging

›Neuroimaging role

›Persistent focal deficit after confirmed normoglycemia

›Persistent encephalopathy after confirmed normoglycemia

›Pancreatic evaluation rarely indicated acutely

›Reserved for suspected insulinoma after sulfonylurea screen is negative

CT

›Targeted CT use

›Head CT

›Persistent neurologic deficit after glucose correction

›Trauma from a collapse or seizure

›Anticoagulation with a fall

›Abdomen CT

07Disposition/dispo28

Admission and observation criteria

›Level of care decisions

›ICU criteria

›Refractory hypoglycemia requiring continuous dextrose infusion

›Recurrent seizures

›Airway compromise

›Significant co-ingestant toxicity

›Inpatient or monitored bed criteria

›Any hypoglycemia requiring dextrose or octreotide

›Any confirmed pediatric ingestion

›Renal or hepatic impairment prolonging clearance

›No reliable supervision at home

Discharge criteria and observation windows

›Safe discharge requirements

›Sustained euglycemia

›Stable glucose above 4.0 mmol/L without dextrose supplementation

›No downward trend after last carbohydrate or octreotide dose

›Minimum 24-hour observation after the last hypoglycemic episode, off dextrose and octreotide, before discharge

›Applies regardless of how rapidly the first episode corrected

›Longer observation for chlorpropamide or extended-release formulations given prolonged half-life

›Pediatric minimum 8-hour observation with glucose checks at least hourly for any confirmed or suspected ingestion, even if asymptomatic at triage

›Extend to full 24-hour observation if any hypoglycemia develops during that window

›Danger of discharge after apparent correction

›A single normal glucose after treatment reflects dextrose effect, not resolution of the underlying secretagogue drive

›Recurrent severe hypoglycemia after premature discharge is a described cause of preventable neurologic injury and death

Transfer criteria

›Transfer indications from non-tertiary EDs

›Octreotide unavailable at the sending facility

08Treatment/t110

Decontamination

›Gastrointestinal decontamination

›Activated charcoal

›1 g/kg orally or by nasogastric tube

›Maximum 50 g

›Indications

›Recent ingestion within 1 to 2 hours

›Protected airway

›Whole bowel irrigation

›Polyethylene glycol electrolyte solution 1.5 to 2.0 L/hour in adults

›Polyethylene glycol electrolyte solution 25 to 40 mL/kg/hour in children

›Indication

›Large extended-release ingestion

Immediate glucose correction

›Rapid correction pathways

›Oral carbohydrate pathway

›Indications

›Awake and able to swallow safely

›Fast-acting carbohydrate 15 g

›Recheck glucose after 15 minutes

›Repeat 15 g if still below 4.0 mmol/L

›IV dextrose pathway

›Indications

›Altered mental status

›Seizure

›Unable to swallow safely

›Dextrose 50% 25 g IV in adults

›Volume 50 mL

›Dextrose 10% 100 to 250 mL IV in adults

›Lower extravasation risk alternative

›Dextrose 10% 2 mL/kg IV in children

›Maximum 250 mL

›Avoid D50 in small children due to hyperosmolar injury risk

›Verify against current pediatric guideline before use

›Glucagon pathway

›Indications

›No IV access

›Glucagon 1 mg IM in adults

›Glucagon 0.03 mg/kg IM in children

›Maximum 1 mg

›Verify against current pediatric guideline before use

›Limitations

›Requires hepatic glycogen stores

›Reduced efficacy with repeated dosing or malnutrition

›Does not suppress ongoing sulfonylurea-driven insulin secretion

Octreotide and secretagogue-specific therapy

›Why dextrose monotherapy fails

›Sulfonylureas close the SUR1 subunit of the pancreatic beta-cell potassium-ATP channel independent of ambient glucose

›Rising serum glucose from a dextrose bolus is itself an independent secretagogue signal on an already-primed beta cell

›Additional endogenous insulin release follows the bolus

›Glucose falls again once the bolus redistributes, producing recurrent or rebound hypoglycemia

›Repeated dextrose boluses alone can perpetuate this cycle rather than resolve it

›Octreotide

›Mechanism

›Activates somatostatin receptors on the beta cell

›Hyperpolarizes the cell and inhibits voltage-gated calcium channels

›Suppresses insulin secretion downstream of the sulfonylurea-blocked potassium-ATP channel rather than competing for it

›Adult dosing

›Octreotide 50 micrograms SC or IV every 6 hours

›Escalate to 100 micrograms SC or IV every 6 hours if recurrent hypoglycemia on the initial dose

›Continuous IV infusion alternative

›Octreotide 1 to 2 micrograms/kg/hour IV for recurrent hypoglycemia despite scheduled dosing

›Typical course 12 to 24 hours based on recurrence risk

›Extend for chlorpropamide or other long-acting agents

›Pediatric dosing

›Octreotide 1 to 1.5 micrograms/kg SC or IV every 6 hours

›Commonly capped at 50 micrograms per dose

›Monitoring

›Glucose trend for rebound every 30 to 60 minutes initially, then every 1 to 2 hours once stable

›Bradycardia risk

›GI side effects including nausea and abdominal cramping

›Indication for initiation

›Any documented hypoglycemia from a known or suspected sulfonylurea ingestion

›Recurrent hypoglycemia after a single dextrose bolus in a patient with diabetes on unclear regimen

›Historic alternative rarely used

›Diazoxide 3 to 8 mg/kg/day PO divided every 8 hours

›Acts by opening the same potassium-ATP channel that sulfonylureas block

›Efficacy may be blunted by competitive occupancy of that channel by high-dose sulfonylurea

›Largely supplanted by octreotide for this indication

Refractory hypoglycemia and troubleshooting

›If hypoglycemia recurs despite scheduled octreotide

›Confirm dose was actually administered and at the correct interval

›Escalate to the higher scheduled dose or convert to continuous IV infusion

›Reconsider ongoing absorption

›Delayed-release or enteric-coated formulation

›Large ingestion with possible pill bezoar

›Reconsider an unrecognized co-ingestant driving hypoglycemia

›Insulin

›Ethanol

›Continue concurrent dextrose infusion titrated to target while octreotide effect is reassessed

›Dextrose 10% infusion starting 100 to 200 mL/hour in adults

›Titrate every 10 to 20 minutes to target glucose 5.0 to 10.0 mmol/L

›Avoid overshoot above 11.1 mmol/L

›Electrolyte and ECG follow-up

›Potassium trend after repeated insulin-driven intracellular shifts

›Hypokalemia risk with recurrent endogenous insulin surges

›ECG for hypokalemia changes with repeated dextrose and endogenous insulin exposure

›Flattened T waves

›U waves

Adjunct and symptom-directed therapy

›Nutritional support

›Long-acting carbohydrate and protein snack after correction if tolerating oral intake

›Continuous enteral or IV dextrose if unable to eat

›Thiamine adjunct

›Indications

›Alcohol use disorder

›Malnutrition

›Thiamine 100 mg IV before or with dextrose in at-risk patients

›Seizure control

›Benzodiazepines first line

›Lorazepam 0.1 mg/kg IV

›Verify against current pediatric guideline before use

›Diazepam 0.15 to 0.2 mg/kg IV

›Verify against current pediatric guideline before use

›Persistent seizure despite benzodiazepines should prompt glucose recheck before antiepileptic escalation

09Special Populations/sp45

Pregnancy

›Pregnancy-specific considerations

›Sulfonylurea use in pregnancy

›Glyburide crosses the placenta more readily than insulin

›Overdose near term carries fetal and neonatal hypoglycemia risk

›Maternal fetal risk

›Placental perfusion depends on maternal perfusion and glucose delivery

›Fetal distress risk with maternal hypoglycemia or seizure

›Treatment safety

›Oral or IV dextrose safe when indicated

›Octreotide used when maternal benefit outweighs limited placental transfer risk

›Neonatal considerations if exposure occurs near delivery

›Neonatal glucose monitoring after delivery

›Disposition modifiers

›Obstetric consultation for recurrent severe episodes

›Fetal assessment in viable gestation with maternal collapse

Geriatric

›Older adult considerations

›Pharmacokinetic risk

›Active renally cleared metabolites of glyburide prolong effect in CKD

›CYP2C9 drug interactions increase sulfonylurea levels

›Atypical presentation

›Confusion without adrenergic symptoms

›Falls as the presenting feature

›Higher harm risk

›Fracture and head injury risk from collapse

›Arrhythmia risk with recurrent severe hypoglycemia

›Disposition modifiers

10Background/b34

Epidemiology

›Epidemiologic features

›Poison control centers in the United States field several thousand sulfonylurea exposure calls annually

›Roughly half of reported ingestions occur in children under 6 years of age

›Glyburide is disproportionately represented among pediatric single-tablet fatalities compared with other sulfonylureas

›Case fatality is rare with appropriate octreotide-based treatment

›Historically higher before octreotide became standard therapy

›High-risk contexts

›Older adults with CKD

›Recent medication changes or refills in intentional overdose

Pathophysiology

›Mechanisms

›Sulfonylurea binding

›Binds the SUR1 subunit of the pancreatic beta-cell potassium-ATP channel

›Channel closure occurs independent of ambient glucose concentration

›Depolarization opens voltage-gated calcium channels and triggers insulin exocytosis

›Pharmacokinetic drivers of prolonged toxicity

›Chlorpropamide has a prolonged half-life of approximately 36 hours

›Glyburide has active metabolites that extend effective duration

›Extended-release glipizide formulations delay and prolong absorption

›High protein binding and hepatic CYP2C9 metabolism create interaction risk

›Rebound hyperinsulinemia after dextrose

›Glucose administration itself acts as a further secretagogue signal on the sulfonylurea-primed beta cell

›Additional insulin release follows each rise in glucose, producing a self-perpetuating cycle without insulin secretion suppression

›Hypokalemia mechanism

›Recurrent endogenous insulin surges drive intracellular potassium shift

Therapeutic Considerations

›Rationale for octreotide over dextrose alone

11Patient Discharge Instructions/pdi28

copy discharge instructions

›Discharge instructions

›What happened

›A medication overdose caused dangerously low blood sugar

›The low blood sugar was treated and monitored until stable

›What to do today

›Eat regular meals with complex carbohydrates and protein

›Do not skip meals for the next 24 hours

›Check glucose more often for the next 24 hours if a home meter is available

›How to treat a mild low at home

›If glucose below 4.0 mmol/L, take fast sugar 15 g

›Recheck in 15 minutes

›Repeat 15 g if still below 4.0 mmol/L

›When to return to the ED

›Confusion

›Seizure

›Fainting

›Glucose below 4.0 mmol/L that does not improve after two rounds of fast sugar

›Repeated lows in the same day

›Unable to keep food or fluids down

›Follow-up

›Primary care or diabetes clinician follow-up within 24 to 72 hours

›Bring the medication bottle to the follow-up visit

Medication and prevention safety

›Safe storage and prevention

›Keep all pills in child-resistant containers

›Store medications locked and out of reach of children

›Never store diabetes pills in a bag or purse a child can access

12References/r12

Clinical guidelines and consensus

›Toxicology society guidance

›American College of Medical Toxicology guidance on octreotide for sulfonylurea-induced hypoglycemia

›American Academy of Clinical Toxicology position statements on gastrointestinal decontamination

›Endocrine and hypoglycemia definitions

›American Diabetes Association Standards of Medical Care in Diabetes current edition hypoglycemia definitions

›International Hypoglycaemia Study Group definitions for clinically significant hypoglycemia below 3.0 mmol/L

›Endocrine Society clinical practice guideline on adult hypoglycemic disorders evaluation and the critical sample concept

Evidence-based sources

›Key evidence base

›Boyle and colleagues demonstrated that octreotide reverses sulfonylurea-induced hyperinsulinemia and prevents recurrent hypoglycemia

›Fasano and colleagues found reduced recurrent hypoglycemic episodes and dextrose requirements with octreotide added to standard therapy compared with standard therapy alone

›Poison center and toxicology textbook data supporting mandatory prolonged observation for pediatric single-tablet ingestion

›Toxicology textbooks and poison center protocols for octreotide and diazoxide dosing standards

Evidence & Review

Evidence & Review