Chronic Complications of Spinal Cord Injury (SCI)

Life Expectancy:
1. Mortality rates highest during 1st year
2. >1 yr, then ~90% of normal

Cardiovascular Complications:
1. Autonomic dysreflexia: SCI>T6 due to uninhibited sympathetic responses
      A. Occurs in 20~70%, >1 m to <1 yr
      B. Not Below T6 b/c intact splanchnic innervation allows for compensatory dilatation of the splanchnic vascular bed.
      C. Prevent stimuli, ex. bladder distention, bowel impaction, pressure sores, bone fracture, or occult visceral disturbances
      D: S/S: HA, diaphoresis, HTN, flushing, piloerection, blurred vision, nasal obstruction, and nausea.
             a. profound bradycardia, OHCA, ICH, seizures
      E. Tx:
           a. Measure BP
           b. Sitting the patient upright to orthostatically lower BP
           c. Search for noxious stimuli
           d. BP meds: nitrates, nifedepine, sublingual captopril, IV hydralazine, IV labetalol
2. CAD
      A. Risk factors:  decreased muscle mass, increased fat, and inactivity, 3~10X more likely. Esp. >T5 level
      B. Tx same as non-SCI pts
3. Orthostatic hypotension
     A: More common in 1st several months of SCI, but can still occur due to excessive bed rest+ low fluid intake
4. Bradycardia (>T6)
     A: baseline pressure reduced



Pulmonary Complications:
1. Pneumonia (30% for 9.5 months)
     A: Impaired cough and difficulty mobilizing lung secretions
     B. Highest within 1st year, but higher risk for life time
     C: Preventions: Chest PT, Vaccinations
          a. Chest PT:  encouragement of deep breathing, manually-assisted coughing (“quad cough”) mechanical insufflator-exsufflator
2. Ventilation failure
     A: Severity depends on level + severity of SCI
     B: Lesser degree: SOB+DOE
3. DVT
     A: LMW heparin for 3 months for pts with complete motor injury
     B: oral vit. K antagonist
         a. Target INR 2.5, range 2 to 3
     C: Intermittent pneumatic compression
         a. For pts contraindication to anticoagulation, adjunct to medical prophylaxis during the 1st two weeks
4. Obstructive or Mixed type Sleep apnea (?)
     A. Cervical SCI: 40~80%, non-obese: 15%

Urinary Complications:
1. Bladder dysfunction (neurogenic bladder):
     A. Impaired sensation for bladder fullness, motor control of bladder and sphincter function
     B. Tx:
         a. Long-term: Clean technique intermittent catheterization (CIC), Q4H
               a) Target: bladder volume <500 cc
               b)Fluid restriction to 2L/day
               c) No caregiver: Foley, change every month, cystoscopy every 2yrs for stones and bladder cancer
         b: Short-term: Condom catheters (for men) and adult diapers
     C: Medications:
         a. Decrease bladder tone, suppress bladder contractions: Anticholinergics
               a) Oxybutynin, tolterodine
                  *Usu. CIC + Anticholinergics
         b. Increase bladder storage: Alpha adrenergics
               a) Ephedrine and phenylpropanolamine
         c. Help complete bladder emptying: Cholinergics
               a) Bethanechol
         d. Help sphincter relaxation, lowering bladder pressures during contraction: Alpha-blockers
               a) Prazosin, terazosin
2. UTI
     A. 2.5 episodes per patient per year
     B. Most frequent source of septicemia in SCI patients, mortality rate (15 percent)
         a. Risk factors: Female, low-frequence + high-volume catheterization, Foley, assisted ICP
     C. Tx: usu. untreated, OBS
         a. Effect of Cranberry juice?
3. Renal and Ureter Stones
     A. Risk factors: recurrent UTIs, indwelling catheters, and immobilization hypercalciuria
     B. Suspect in presence of increased limb spasticity and episodes of autonomic dysreflexia
4. Vesicoureteral reflux
     A. 25% in SCI pts
     B. Risk factors: high bladder pressures and recurrent UTI
     C. Higher risk of pyelonephritis and renal dysfunction
     D: Tx: Foley/Surgery
         a. Oxybutynin may reduce bladder pressure caused by bladder spasms with an indwelling catheter
5. Renal failure
     A. Cumulative incidence: increases with time since SCI, 25% at 20 years
     B. Risk factors: Indwelling urethral catheters, vesicoureteral reflux, and advanced age

Gastrointestinal Complications:
1. Bowel dysfunction:
     A. Above conus medullaris (L1-L2):
        a. Spinal cord and bowel nerves connected --> hyperreflexic pelvic muscle contraction and inability to voluntarily relax the external anal sphincter --> constipation + fecal impaction
     B. Below conus medullaris:
        a. Areflexic bowel --> slower transit, decreased sphincter tone, and constipation with frequent incontinence
     C. Tx based on preinjury bowel habits:
        a. A typical routine may begin at a regular time point each day with insertion of a chemical stimulant rectal suppository.
        b. After several minutes, digital stimulation with slow, gentle rotation of the finger for 15 to 60 seconds,  repeat every 5 ~ 10 minutes, until stool evacuation is complete.
        c. Abdominal massage, deep breathing, Valsalva maneuver, and forward-leaning position may assist evacuation
     D. Oral bowel meds are used at inital phase, then slowly taper
     E: Others:
        a. Food: high fiber (30g), low dairy + fat   
        b. Fluid: depends on bladder, but target U/O: 2-3L/day
        c. Constipation treatment
2. Serious abdominal complications:
     A. Cholecystitis/upper GIB/pancreatitis/appendicitis
     B. 10% of deaths following SCI
     C. Increased prevalence of gallstones

Bone Complications:
1. Osteoporosis
     A. Increases risk of lower ext. fractures, etiology unclear
     B. Risk factors: Older age, higher spinal level of injury, lesser degrees of spasticity, and longer chronicity of the injury
2. Symptomatic hypercalcemia and hypercalciuria
     A. S/S: N/V, anorexia, lethargy, polyuria, renal stone
3. Heterotopic Ossification
    A. Definition: deposition of bone within the soft tissue around peripheral joints
    B. 50% of SCI pts, beginning at 12 wks after injury  
       a. 10% have clinical symptoms 
    C. Large joints below the level of injury, esp. the hip
    D. DDx: DVT, cellulitis, infection, hematoma, and tumor
       a. Specific: triple phase bone scan, (elevated ALP)
    E. Mechanism: activation of osteoprogenitor stem cells lying dormant within the affected soft tissues??
    F. Tx:
       a. Passive ROM exercise 
       b.indomethacin 75 mg QD x 3 wks
       c. Bisphosphonates    
       d. rofecoxib 25 mg QD x 4 wks??
       e. Refractory: surgery
            a) Most still have recurrence

Musculoskeletal Complications:
1. Muscle Contractures
   A. Etiology: reorganization of the collagen tissue matrix occurs when muscle lies in the shortened position for an extended period of time. Both immobility and spasticity contribute to this occurrence
   B. Tx: positioning, ROM exercise, splinting
       a. Established contractures: surgery
2. Tendon injuries
   A. Due to repetitive over-use, shoulder most common (75%)
3. Pressure Ulcers
   A. Risk factors:  Shear, friction, poor nutrition, and changes in skin physiology below the level of the lesion
   B. 1/3 of pts have multiple pressure sores
      a. Location:
           a) Ischium – 31 percent
           b) Trochanter - 26 percent
           c) Sacrum - 18 percent
           d) Heel - 5 percent
           e) Malleolus - 4 percent
           f) Feet - 2 percent
 4. Spasticity
   A. disruption of descending inhibitory modulation of the alpha motor neurons --> hyperexcitability --> increased muscle tone and spasms
   B. Tx:
      a. PT, stretching and wearing braces
      b. Medications: oral/ IT Baclofen, diazepam
      c. Chemodenervation
      d. Surgery
5. Pain Syndromes
   A. Months to years after SCI
   B. Tx: Pregabalin, gabapentin, anti-depressants, opiates

Neurological Complications:
1. Syringomyelia
   A. Definition: delayed progressive intramedullary cystic degeneration, interval since SCI can vary from months to yrs
   B. S/S:  worsening motor, sensory, bowel, and bladder deficits and pain
   C. Tx: reducing expansile intracystic pressure and improving CSF flow
       a. Surgery: shunt placement, lysis of subarachnoid adhesions, cyst fenestration, and dural augmentation
2. Progressive posttraumatic myelomalacic myelopathy (Marshy cord syndrome)
   A. Occurs less often

Psychiatric Complications:
1. Depression, suicide, drug addiction, and divorce
   A. 20 to 45% of pts, can occur within a month after SCI
   B. Suicide: leading cause of death in traumatic SCI patients younger than 55 yrs
       a. 75% occur within the first 5 yrs of injury

Others:
1. Thermoregulatory dysfunction

Prognosis:
1. Level and completeness of the SCI

(Reference: Uptodate)