**3. Preoperative consideration**

Three type of paediatric CHD patients are expected to come for evaluation.

	- a. ToF with BT shunt
	- b. Atrial septostomy for TGA

Preoperative evaluation should include detailed information about cardiac lesion, altered physiology and its implications. There are few questions which should be clearly answered during preoperative evaluation of these CHD patients. These includes


Fatigue, headache, visual disturbances, depressed mentation and paraesthesia of toes and fingers are presenting symptoms of polycythaemia. History of cyanosis and congestive heart failure (CHF) are major manifestations of CHD. Fatigue and dyspnoea on feeding and irritability indicate poor functional status. Cyanosis occurs due to decrease pulmonary flow anatomically or functionally (Mixing lesion). Cyanosis may be permanent or appear intermittently. Cyanosis may not be seen in new born due to presence of faetal haemoglobin which is highly saturated at a given PaO2.

High pulmonary flow leads to pulmonary edema. Failure to thrive and feeding problems are common in patients with history of repeated pulmonary congestion. Patient may presents with tachycardia, tachypnoea, irritability, cardiomegaly and hepatomegaly. The right ventricular function should also be assessed as it is equally important in paediatric CHD patient.

Try to avoid dehydration in cyanotic CHD patients by allowing clear liquids two hours prior to surgery (Table 1). Children also have low glycogen stores which makes them vulnerable to hypoglycemia. If timing of surgery uncertain then start an intravenous line and give glucose containing solution. Midazolam10 11 is a preferred sedative in the doses of 0.5 to 1mg/kg or even higher doses in few studies given orally half hour before surgery (Table 2). If patient is on prostaglandin (PGE1) infusion then it should be continued.


Table 1. NPO Orders

58 Perioperative Considerations in Cardiac Surgery

e. Pulmonary Stenosis (PS) f. Aortic Stenosis (AS) g. Coarctation of the Aorta

b. Transposition of the Great Arteries (TGA)

a. Tetralogy of Fallot, Pulmonary atresia 3. Inadequate or obstruction to systemic blood flow

1. Excessive Pulmonary Blood Flow a. VSD, ASD, PDA, PAPVR 2. Inadequate Pulmonary Blood Flow

a. Coarctation of Aorta

**3. Preoperative consideration** 

a. ToF with BT shunt

1. Patients with uncorrected cardiac defect 2. Patients who had previous palliative surgery

b. Atrial septostomy for TGA

requiring certain procedures9

b. Direction and amount of shunting

f. Coagulation abnormalities

h. Functional status of the patient

e. Degree of hypoxaemia, Polycythaemia

c. Presence and severity of pulmonary hypertension d. To what extent pulmonary flow reduced or increased?

4. Abnormal Mixing a. TGA

procedure

c. Total Anomalous Pulmonary Venous Return(TAPVR)

f. Uncommon, each <1% of CHD, pulmonary atresia, Ebstein's anomaly.

Three type of paediatric CHD patients are expected to come for evaluation.

during preoperative evaluation of these CHD patients. These includes

3. Patients in whom total correction has been done but they may have residual defects

Preoperative evaluation should include detailed information about cardiac lesion, altered physiology and its implications. There are few questions which should be clearly answered

a. Complete understanding of the anatomical changes due to cardiac defect or palliative

g. What associated pathophysiological findings likely will influence the management?

Fatigue, headache, visual disturbances, depressed mentation and paraesthesia of toes and fingers are presenting symptoms of polycythaemia. History of cyanosis and congestive heart failure (CHF) are major manifestations of CHD. Fatigue and dyspnoea on feeding and irritability indicate poor functional status. Cyanosis occurs due to decrease pulmonary flow

**2.2 Classification on the basis of pulmonary and systemic flow** 

**2.1.2 Cyanotic CHD**  a. Tetralogy of Fallot

d. Tricuspid Atresia e. Truncus Arteriosus


Table 2. Premedication orders
