CYANOTIC SPELLS paroxysmal hyperpnea hypoxic spells anoxic spells blue spells.

CYANOTIC SPELLS

• paroxysmal hyperpnea

• hypoxic spells

• anoxic spells

• blue spells

CYANOTIC SPELLS

rate & depth of respiration

increasing cyanosis

Limpness , syncope, -------- convulsions, CVA

------------------------------ DEATH

CYANOTIC SPELLS -- CLINICAL PROFILE

Morgan et al - Circulation 1965 :31;66-69

190 pts requiring shunt

38% had spells ---- 80 % TOF & 20% tricuspid atresia

Age -- onset -- 2 months – 1 year

Time of day -- morning hours

Duration --- 15- 60 min

Ppting factors -- awakening,crying , defecation , feeding, unpleasant stimuli eg. needle prick

CYANOTIC SPELLS -- CLINICAL PROFILE

• not always correlate with severity of TOF

• infrequent in high altitude natives

due to diminished sensitivity of respiratory centre to hypoxia

• frequency decreases after morning hours as respiratory centre gets adapted

CYANOTIC SPELLS -physiology

HYPERVENTILATION is the main factor

Normal – sleep is attended by reduction in ventilation

PaCO2 , PaO2,SaO2,pH

On waking up reverse occurs

CYANOTIC SPELLS -physiology

TOF

Sleep - reduced O2 demend --- better SaO2

Waking up --- ventilation, activity

PaCO2, SaO2, PaO2,pH

CYANOTIC SPELLS -physiology

Effect

Effect of hyperventilation

Normal -- SaO2 , PaO2 & pH PaCO2

TOF -- consistent fall in SaO2

Hyperventilation venous return to RV

R L shunt PCO2 , PaO2, pH,Sao2

CYANOTIC SPELLS -physiology

TOF

High pulm . resistance

RVOT resistance( highand fixed )

vasc . Resistance( low )

Pulm.resistance > systemic

Systemic vascular resistance is dynamic

Any change in SVR modifies the right to left shunt

CYANOTIC SPELLS -physiology

Hyperpnea

venous return to RV with fixed RVOT resistance

R L shunt

aPCO2 , PaO2, pH,Sao2

SVR

CYANOTIC SPELLS -physiology

• Hyperpnea

• increased activity O2 requirement PCO2 , PaO2, pH,Sao2

• ? RVOT “ spasm ”X spells seen in pulmonary atresia also

• Tachycardia --- increased RVOT contractilityincreased C.O.

CYANOTIC SPELLS -TREATMENT

Hyperpnea

venous return to RV with fixed RVOT resistance

R L shunt

aPCO2 , PaO2, pH,Sao2

SVR

X -

CYANOTIC SPELLS -TREATMENT

Hyperpnea

venous return to RV with fixed RVOT resistance

R L shunt

aPCO2 , PaO2, pH,Sao2

SVRX

X

CYANOTIC SPELLS -TREATMENT

Hyperpnea

venous return to RV with fixed RVOT resistance

R L shunt

aPCO2 , PaO2, pH,Sao2

SVR x

CYANOTIC SPELLS -TREATMENT

• knee chest position

• O2 inhalation

• morphine

•propranolol

• alpha stimulants

• sodabicarb

• general anesthesia

• emergency shunt in recurrent spells

CYANOTIC SPELLS -TREATMENT

Hyperpnea

venous return to RV with fixed RVOT resistance

R L shunt

aPCO2 , PaO2, pH,Sao2

SVR

X - MORPHINE

X

CYANOTIC SPELLS -TREATMENT

Knee – chest position

• intra abdominal pressure

SVR reduced R > L shunt splanchnic venous return – high

O2 saturation

• kinking of femoral veins reduces venous return lower limbs( low O2 saturation)

CYANOTIC SPELLS -TREATMENT

PROPRANOLOL

• 0.2 mg/kg IV

• reduces HR, RVOT contractility

• increases SVR

More useful in those with

• little cyanosis at rest• marked reduction in SaO2 with activity / hyperventilation

CYANOTIC SPELLS

RECURRENT SPELLS AT HOME –GET SPONTANEOUSLY ABORTED

SPELLS IN HOSPITALS — LAND UP IN ANESTHESIA

PARADOX