Diabetes Mellitus: Management

Introduction

1. Classification and Initial Assessment

• Type 1 DM — absolute insulin deficiency (autoimmune β-cell destruction); insulin is mandatory from diagnosis.
• Type 2 DM — relative insulin deficiency with peripheral resistance; managed stepwise, beginning with lifestyle changes and oral agents.

2. Non-Pharmacological Management

• Diet: High-fiber, low-glycemic index foods; caloric restriction in obese patients.
• Exercise: Regular physical activity reduces insulin resistance; must be balanced with caloric intake and drug regimens.
• Weight management: Even modest weight loss (5–10%) substantially improves glycemic control in Type 2 DM.
• Bariatric surgery: Considered in severe obesity with inadequately controlled Type 2 DM when pharmacotherapy fails. — Guyton and Hall Textbook of Medical Physiology

3. Pharmacological Management

Type 1 DM — Insulin-Dependent

┌─────────────────────────────────────────────────────────┐
│             TYPE 1 DM MANAGEMENT FLOWCHART              │
└─────────────────────────────────────────────────────────┘
         Newly Diagnosed Type 1 DM
                   │
                   ▼
     Start Insulin (Basal-Bolus Regimen)
     • Basal: Glargine / Detemir (once daily)
     • Bolus: Aspart / Lispro (pre-meals)
                   │
                   ▼
       Monitor Blood Glucose + HbA1c
      (Target HbA1c < 7%; FBG 90–130 mg/dL)
                   │
             ┌─────┴──────┐
          Achieved?      Not Achieved?
             │                │
      Continue + annual   Adjust dose /
      complication        consider CSII
      screening          (insulin pump)

Type 2 DM — Stepwise Pharmacotherapy

┌─────────────────────────────────────────────────────────────┐
│             TYPE 2 DM MANAGEMENT FLOWCHART                  │
└─────────────────────────────────────────────────────────────┘
     Newly Diagnosed Type 2 DM
              │
              ▼
  Lifestyle Modification (Diet + Exercise)
  ± Metformin 500 mg OD/BD (first-line)
              │
              ▼
       Reassess HbA1c at 3 months
              │
       ┌──────┴───────┐
   HbA1c < 7%     HbA1c ≥ 7%
       │               │
   Continue        Add Second Agent
   monitoring      based on comorbidity:
                   │
        ┌──────────┴───────────┐
    Heart Failure /        No major
    Renal Disease          comorbidity
        │                      │
   SGLT-2 inhibitor       Sulfonylurea
   (empagliflozin /       (glipizide 5 mg OD)
    canagliflozin)        OR GLP-1 agonist
        │                      │
        └──────────┬───────────┘
                   ▼
         Still not at target?
                   │
                   ▼
           Add/Intensify Insulin

4. Monitoring and Targets

• HbA1c < 7% (or < 7.5% in older adults with comorbidities)
• Fasting glucose: 80–130 mg/dL
• 2-hour postprandial: < 180 mg/dL

5. Complications and Organ-Specific Management

┌──────────────────────────────────────────────────┐
│        DIABETIC COMPLICATIONS FLOWCHART          │
└──────────────────────────────────────────────────┘
         Diabetes Diagnosis
                │
    ┌───────────┼────────────┐
    ▼           ▼            ▼
 Nephropathy  Retinopathy  Neuropathy
    │           │            │
 Microalbumi-  Annual       Peripheral:
 nuria screen  fundoscopy   Pregabalin /
    │           │           Duloxetine
 ACEi/ARB +   Refer to     Autonomic:
 BP control   ophthalmol.  Symptomatic Rx
    │           │            │
    └───────────┼────────────┘
                ▼
       Macrovascular Disease
     (CAD, Stroke, Peripheral
         Arterial Disease)
                │
       Statin + Antiplatelet
       + BP control (<130/80)

• Nephropathy: ~50% of end-stage renal disease in the US is diabetic in origin. ACE inhibitors reduce microalbuminuria and slow progression. — ROSEN's Emergency Medicine
• Retinopathy: Leading cause of adult blindness; severity directly related to glycemic control. Background retinopathy → proliferative retinopathy → vitreous hemorrhage. Referral to ophthalmology is mandatory.
• Neuropathy: Peripheral symmetric neuropathy affects 15–60% of patients. First-line analgesics: duloxetine 60 mg/day or pregabalin up to 600 mg/day, both achieving meaningful pain control in >50% of patients.

6. Inpatient and Special Situations

• Inpatient hyperglycemia: Target blood glucose 140–180 mg/dL; use insulin infusion in critically ill patients.
• CKD patients: Avoid metformin; use insulin ± GLP-1 agonists.
• Heart failure: SGLT-2 inhibitors (empagliflozin, canagliflozin) show documented mortality benefit.
• Perioperative period: Hold oral agents; use insulin sliding scale.

Conclusion

• ROSEN's Emergency Medicine: Concepts and Clinical Practice — Management of Diabetes Mellitus
• Goldman-Cecil Medicine, International Edition — Inpatient Management of Diabetes
• Harrison's Principles of Internal Medicine, 22E (2025) — Glycemic Control and Complications
• Guyton and Hall Textbook of Medical Physiology — Type 2 Diabetes Management

Intratympanic Therapy

Introduction

Rationale and Pharmacokinetic Basis

Technique of Intratympanic Injection

┌────────────────────────────────────────────────────────┐
│         INTRATYMPANIC INJECTION TECHNIQUE              │
└────────────────────────────────────────────────────────┘

STEP 1: Patient positioned supine, head turned 45°
           away from injected ear

STEP 2: Local anaesthetic (topical EMLA or
          phenol) applied to tympanic membrane

STEP 3: Under microscopic or endoscopic guidance,
          a 25–27 gauge needle inserted into the
          POSTEROINFERIOR quadrant of TM

STEP 4: Drug injected slowly (0.3–0.5 mL)
          filling the middle ear space

STEP 5: Patient instructed to remain still
          with head tilted 45° for 20–30 mins
          (promotes contact with round window)

STEP 6: Patient advised NOT to swallow or
          yawn (prevents Eustachian tube
          drainage of drug)

         ┌──────────────────┐
         │  Tympanic        │
         │  Membrane        │
         │                  │
         │  [Posteroinferior│◄── Needle entry
         │   quadrant]      │
         │                  │
         └────────┬─────────┘
                  │ Drug diffuses
                  ▼
         ┌──────────────────┐
         │  Middle Ear      │
         │  Space           │
         └────────┬─────────┘
                  │ Crosses
                  ▼
         ┌──────────────────┐
         │  Round Window    │
         │  Membrane        │
         └────────┬─────────┘
                  │
                  ▼
         ┌──────────────────┐
         │  Scala Tympani   │
         │  (Perilymph)     │
         └──────────────────┘

Agents Used and Their Indications

┌──────────────────────────────────────────────────────────────────┐
│              IT THERAPY — AGENTS & INDICATIONS                   │
└──────────────────────────────────────────────────────────────────┘
                     Intratympanic Therapy
                           │
          ┌────────────────┴────────────────┐
          ▼                                 ▼
    CORTICOSTEROIDS                    AMINOGLYCOSIDES
    (Dexamethasone /                   (Gentamicin)
    Methylprednisolone)
          │                                 │
    ┌─────┴──────┐                    ┌─────┴──────┐
    ▼            ▼                    ▼            ▼
 ISSNHL      Ménière's          Ménière's      Chemical
 (primary    Disease            Disease        labyrinthectomy
 or salvage  (vertigo           (intractable   (vestibular
 therapy)    control)           vertigo)       ablation)

1. Intratympanic Corticosteroids

• ISSNHL: Used as primary therapy or salvage treatment after failure of systemic steroids. Prospective RCTs confirm that IT methylprednisolone improves hearing in patients who fail oral steroids. — Cummings Otolaryngology
• Ménière's disease: Vertigo control achieved in 82% vs. 57% with saline placebo in a randomized trial. Effect on hearing and tinnitus is minimal. May require repeat injections every 3 months.

• 4–5 weekly injections of dexamethasone 2 mg/mL
• Vertigo relief in 80%; tinnitus reduction in 74%

2. Intratympanic Gentamicin

• Wu & Minor: 90% complete vertigo control; profound SNHL in only 3%
• Nedzelski et al.: 83% vertigo control; 10% profound hearing loss
• Superior to dexamethasone for vertigo control (RCT, Casani et al.)

Comparison of IT Agents

Complications

Complications of IT Therapy
├── Injection-related
│   ├── Tympanic membrane perforation (usually self-healing)
│   ├── Pain / discomfort at injection site
│   ├── Dizziness (transient, caloric effect of cold drug)
│   └── Otitis media (rare)
└── Drug-specific
    ├── Steroids: minimal; no documented ototoxicity
    └── Gentamicin: sensorineural hearing loss (dose-dependent),
                    oscillopsia, imbalance (permanent in ablative cases)

Conclusion

• Cummings Otolaryngology Head and Neck Surgery — Chapters 158, 167 (Intratympanic Drug Delivery; Ménière Disease)
• K.J. Lee's Essential Otolaryngology — Inner Ear, ISSNHL
• Harrison's Principles of Internal Medicine 22E — Sensorineural Hearing Loss

Prosthetic Phonatory Devices

Introduction

Anatomy of Voice Rehabilitation After Laryngectomy

POST-LARYNGECTOMY ANATOMY
─────────────────────────
   Oral cavity
        │  (articulation)
   Pharynx / PE segment  ◄── Vibrates to produce voice
        │
   Oesophagus
        │
   ┌────┴───────────────────┐
   │  Tracheoesophageal     │
   │  Party Wall            │
   │  [TEP / Voice Prosth.] │◄── One-way valve
   └────┬───────────────────┘
        │ (exhaled lung air redirected)
   Trachea
        │
   Tracheostoma
   (permanent, anterior neck)
        │
   Lungs (air source)

1. Tracheoesophageal Voice Prosthesis (TEP / TEVP)

Mechanism

Types

TRACHEOESOPHAGEAL VOICE PROSTHESIS — KEY COMPONENTS
─────────────────────────────────────────────────────
  Tracheal flange ──┐
                    ├── Shaft (8 mm standard length)
  Silicone valve ───┤   traverses party wall
                    └── Esophageal flange

  ← Trachea side │ Esophagus side →
  (air IN)       │  (air enters to vibrate PE segment)
                 │
             One-way valve
         (opens on exhalation,
          closes at rest to prevent
          liquid retrograde flow)

TEP Procedure — Primary vs. Secondary

• Primary TEP: Performed at the time of laryngectomy. Immediate VP fitting stabilizes the party wall and allows voicing by postoperative day 10.
• Secondary TEP: Performed ~4 weeks post-laryngectomy in the outpatient clinic under flexible esophagoscopy guidance, using a Seldinger-type trocar technique.

Heat and Moisture Exchanger (HME)

Outcomes

• TE voice achieves the gold standard for voice rehabilitation after laryngectomy.
• Voice production possible on the day of prosthesis insertion in many patients.
• Control of vertigo: >80% voice success rates in experienced centres.
• Cricopharyngeal spasm can impair fluency; treated with botulinum toxin injection percutaneously or endoscopically.

Complications

COMPLICATIONS OF TE VOICE PROSTHESIS
───────────────────────────────────────
Device complications
├── Candida biofilm → valve incompetence → leakage THROUGH prosthesis
├── Periprosthetic leakage (around the device, not through it)
├── TEP enlargement / fistula widening
└── Prosthesis dislodgement

Patient/anatomy complications
├── Cricopharyngeal spasm → poor voice fluency
├── Stomal stenosis
└── Pharyngeal stenosis (more common after fasciocutaneous reconstruction)

2. Artificial Electrolarynx

• Immediately usable postoperatively — no surgical procedure required
• Produces a monotone, robotic-sounding voice
• Used as a temporary bridge while awaiting TEP, or as long-term option in patients unable to undergo TEP
• Types: neck-type (most common) and intraoral (via tube into corner of mouth)

3. Esophageal Speech

Comparison of Alaryngeal Voice Methods

Conclusion

• Cummings Otolaryngology Head and Neck Surgery — Chapters 111, 158 (Voice Rehabilitation; Prosthetic Voice)
• Schwartz's Principles of Surgery, 11th Ed. — Specific Considerations: Laryngectomy Speech Rehabilitation
• Bailey and Love's Short Practice of Surgery, 28th Ed. — Alaryngeal Speech Methods