Healthcare Cdss Patterns

interface DrugInteractionPair {  drugA: string;           // generic name  drugB: string;           // generic name  severity: 'critical' | 'major' | 'minor';  mechanism: string;  clinicalEffect: string;  recommendation: string;}
function checkInteractions(  newDrug: string,  currentMedications: string[],  allergyList: string[]): InteractionAlert[] {  if (!newDrug) return [];  const alerts: InteractionAlert[] = [];  for (const current of currentMedications) {    const interaction = findInteraction(newDrug, current);    if (interaction) {      alerts.push({ severity: interaction.severity, pair: [newDrug, current],        message: interaction.clinicalEffect, recommendation: interaction.recommendation });    }  }  for (const allergy of allergyList) {    if (isCrossReactive(newDrug, allergy)) {      alerts.push({ severity: 'critical', pair: [newDrug, allergy],        message: `Cross-reactivity with documented allergy: ${allergy}`,        recommendation: 'Do not prescribe without allergy consultation' });    }  }  return alerts.sort((a, b) => severityOrder(a.severity) - severityOrder(b.severity));}

interface DoseValidationResult {  valid: boolean;  message: string;  suggestedRange: { min: number; max: number; unit: string } | null;  factors: string[];}
function validateDose(  drug: string,  dose: number,  route: 'oral' | 'iv' | 'im' | 'sc' | 'topical',  patientWeight?: number,  patientAge?: number,  renalFunction?: number): DoseValidationResult {  const rules = getDoseRules(drug, route);  if (!rules) return { valid: true, message: 'No validation rules available', suggestedRange: null, factors: [] };  const factors: string[] = [];
  // SAFETY: if rules require weight but weight missing, BLOCK (not pass)  if (rules.weightBased) {    if (!patientWeight || patientWeight <= 0) {      return { valid: false, message: `Weight required for ${drug} (mg/kg drug)`,        suggestedRange: null, factors: ['weight_missing'] };    }    factors.push('weight');    const maxDose = rules.maxPerKg * patientWeight;    if (dose > maxDose) {      return { valid: false, message: `Dose exceeds max for ${patientWeight}kg`,        suggestedRange: { min: rules.minPerKg * patientWeight, max: maxDose, unit: rules.unit }, factors };    }  }
  // Age-based adjustment (when rules define age brackets and age is provided)  if (rules.ageAdjusted && patientAge !== undefined) {    factors.push('age');    const ageMax = rules.getAgeAdjustedMax(patientAge);    if (dose > ageMax) {      return { valid: false, message: `Exceeds age-adjusted max for ${patientAge}yr`,        suggestedRange: { min: rules.typicalMin, max: ageMax, unit: rules.unit }, factors };    }  }
  // Renal adjustment (when rules define eGFR brackets and eGFR is provided)  if (rules.renalAdjusted && renalFunction !== undefined) {    factors.push('renal');    const renalMax = rules.getRenalAdjustedMax(renalFunction);    if (dose > renalMax) {      return { valid: false, message: `Exceeds renal-adjusted max for eGFR ${renalFunction}`,        suggestedRange: { min: rules.typicalMin, max: renalMax, unit: rules.unit }, factors };    }  }
  // Absolute max  if (dose > rules.absoluteMax) {    return { valid: false, message: `Exceeds absolute max ${rules.absoluteMax}${rules.unit}`,      suggestedRange: { min: rules.typicalMin, max: rules.absoluteMax, unit: rules.unit },      factors: [...factors, 'absolute_max'] };  }  return { valid: true, message: 'Within range',    suggestedRange: { min: rules.typicalMin, max: rules.typicalMax, unit: rules.unit }, factors };}

interface NEWS2Input {  respiratoryRate: number; oxygenSaturation: number; supplementalOxygen: boolean;  temperature: number; systolicBP: number; heartRate: number;  consciousness: 'alert' | 'voice' | 'pain' | 'unresponsive';}interface NEWS2Result {  total: number;           // 0-20  risk: 'low' | 'low-medium' | 'medium' | 'high';  components: Record<string, number>;  escalation: string;}

describe('CDSS — Patient Safety', () => {  INTERACTION_PAIRS.forEach(({ drugA, drugB, severity }) => {    it(`detects ${drugA} + ${drugB} (${severity})`, () => {      const alerts = checkInteractions(drugA, [drugB], []);      expect(alerts.length).toBeGreaterThan(0);      expect(alerts[0].severity).toBe(severity);    });    it(`detects ${drugB} + ${drugA} (reverse)`, () => {      const alerts = checkInteractions(drugB, [drugA], []);      expect(alerts.length).toBeGreaterThan(0);    });  });  it('blocks mg/kg drug when weight is missing', () => {    const result = validateDose('gentamicin', 300, 'iv');    expect(result.valid).toBe(false);    expect(result.factors).toContain('weight_missing');  });  it('handles malformed drug data gracefully', () => {    expect(() => checkInteractions('', [], [])).not.toThrow();  });});

const alerts = checkInteractions('warfarin', ['aspirin', 'metformin'], ['penicillin']);// [{ severity: 'critical', pair: ['warfarin', 'aspirin'],//    message: 'Increased bleeding risk', recommendation: 'Avoid combination' }]

const ok = validateDose('paracetamol', 1000, 'oral', 70, 45);// { valid: true, suggestedRange: { min: 500, max: 4000, unit: 'mg' } }
const bad = validateDose('paracetamol', 5000, 'oral', 70, 45);// { valid: false, message: 'Exceeds absolute max 4000mg' }
const noWeight = validateDose('gentamicin', 300, 'iv');// { valid: false, factors: ['weight_missing'] }

const result = calculateNEWS2({  respiratoryRate: 24, oxygenSaturation: 93, supplementalOxygen: true,  temperature: 38.5, systolicBP: 100, heartRate: 110, consciousness: 'voice'});// { total: 13, risk: 'high', escalation: 'Urgent clinical review. Consider ICU.' }