Anaesthesiology Intensive Therapy, 2009,XLI,3; 102-106

Complications during anaesthesia for diagnostic and interventional cardiac procedures in children with congenital heart defects

*Małgorzata Świątnicka-Lucińska1, Michał Markiewicz1, Tomasz Moszura2, Wojciech Krajewski1


1Department of Anaesthesiology and Intensive Medical Therapy, Institute of Polish Mother’s Health Centre in Łódź


2Department of Cardiology, Institute of Polish Mother’s Health Centre in Łódź

  • Table 1. Types of diagnostic and interventional procedures
  • Table 2. Types of anaesthesia
  • Table 3. Incidence of complications and deaths according to physical status of patients
  • Table 4. Technique-related circulatory complications
  • Table 5. Incidence of complications and deaths in individual age groups
  • Fig. 1. Causes of cardiac arrest according to heart defects
  • Fig. 2. Causes of cardiac arrest according to haemodynamic abnormalities

Background. Cardiac catheterisation, while enabling dynamic evaluation of the cardiovascular system, is also commonly performed for interventional procedures in all age groups. The aim of this study was to analyse the incidence and spectrum of complications occurring during general anaesthesia in children undergoing cardiac catheterisation.

Methods. We retrospectively reviewed the medical charts of 1622 consecutive patients, anaesthetised for 817 diagnostic, and 805 interventional cardiac procedures. Data on patient- and procedure-related variables affecting the risk of complications was collected. We analysed the influence of age, physical status, type of heart defect, type of procedure, and anaesthetic protocol on the incidence of complications.

Results. Serious complications occurred in 5 patients undergoing diagnostic procedures and in 24 undergoing interventional procedures, with infants being the most affected (21 cases). The most frequent complication was acute heart failure related to the catheterisation. In 2 cases, pneumothorax followed central venous catheter insertion. There were 14 cardiac arrests requiring cardiopulmonary resuscitation, resulting in three deaths.

Conclusions. The results show that diagnostic cardiac catheterisation and interventional procedures are associated with a low risk of complications (1.78%) and a low mortality rate (0.18%). 

Thanks to advances in perinatal medicine, cardiology and cardiac surgery, increasingly high numbers of newborns and infants undergo repair procedures for heart defects. Despite the development of non-invasive diagnostic methods, catheterization remains indispensable, especially in the multi-stage surgical treatment of multiple heart defects. It enables to perform interventional cardiac  procedures in patients with selected defects of the cardiovascular system; moreover, in many cases it is the only method of management in children who cannot be subjected to surgical procedures due to their critical condition or age.

In spite of the use of safer contrast media, modern equipment and improved methods of examination and anaesthesia, the life threatening events are not completely avoidable.

The objective of the present study was to analyse the complications and factors leading to them during anaesthesia for diagnostic and interventional cardiac procedures.

METHODS

The retrospective study was carried out. Children were prepared and anesthetized according to the definite protocol. Examinations and procedures were performed under general anaesthesia. Critically ill children, those with circulatory insufficiency symptoms scheduled for examinations on an urgent or emergency basis, as well as neonates and infants below 6 months of age were not premedicated. Children above 6 months of age received midazolam 30 min before the procedure. General anaesthesia with endotracheal intubation was applied in neonates and infants below 1 year of age, in all patients qualified for cardiac interventional procedures, and those with symptoms of circulatory failure scheduled for urgent and emergency examinations.

Anaesthesia was induced with midazolam, ketamine and fentanyl, i.v. Endotracheal intubation was facilitated with atracurium. Doses of drugs were age- and body weight-dependent. During anaesthesia, lung ventilation was carried out using the mixture of air and oxygen.  FEO2 values were adjusted to the clinical status and heart defect; the pressure of oxygen and carbon dioxide in blood and peripheral blood saturation were periodically monitored. Anaesthesia was maintained with sevoflurane, 1-3 % in the respiratory mixture and muscle relaxation with fractionated doses of atracurium. Patients with efficient circulation  scheduled for elective diagnostic procedures received general anaesthesia with spontaneous  respiration and  passive oxygen therapy; younger infants (1-8 years of age) were anaesthetized intravenously – the continuous ketamine infusion, older children (> 8 years of age) - intravenously with the continuous propofol infusion. Additionally, a cardiologist performing catheterization anaesthetized locally the place of endovascular catheter introduction with 1% solution of lidocaine.

Non-invasive monitoring (pulsoxymetry, indirect blood pressure measurements, ECG, body temperature) was initiated before the induction of anaesthesia. In children with severe circulatory insufficiency requiring vascular agents, arterial pressure was measured invasively.

After the diagnostic or interventional procedure, patients were sent to the postoperative care unit or recovery room and observed for several hours. Those conscious, with efficient respiration and stable circulation (appropriately to the heart defect and pre-procedure status) were transferred to the cardiac intensive surveillance unit.   

Invasive procedures were carried out by the team of two interventional cardiologists. During examinations, pressures and blood saturation in cardiac vessels and cavities were measured.  A non-iodine contrast medium was injected through the femoral vein, internal jugular vein or femoral artery according to the anatomy of cardiac defects, purpose and type of the procedure (diagnostic or interventional). Examinations were X-ray-guided and the single-plane angiograph imaging was used.

Acute circulatory or respiratory failures during the procedure requiring resuscitation were considered severe complications.

RESULTS

The study material included charts of 1622 children who underwent 817 diagnostic and 805 interventional procedures (Table 1). The following age groups were distinguished: newborns – 315 (19.9%), infants < 1 year of age – 477 (29.4%), infants aged 1-8 years – 485 (29.9%), children > 8 years of age – 345 (21.2%); 1233 (76.1%) children with cyanotic and 389 (23.9%) with non-cyanotic cardiac defects; in the majority of cases, the inhalation method of anaesthesia was used (Table 2). The incidence of complications versus pre-procedure physical status of children is presented in Table 3.

The complications observed were as follows: circulatory – in 26 (89.6%) patients (Table 4), pneumothorax during institution of central venous line – in 2 (6.8%), heart defect-related anoxic attack in 1 (3.6%) child. The factor increasing the risk of complications was severe general status before the procedure (ASA V) – 4 patients (14.3%). Complications were observed in 5 patients undergoing diagnostic and 24 patients during interventional procedures.  Table 5 presents the number of complications and deaths in individual age groups.

Out of 29 (1.78%) patients with complications, 14 (0.86%) had cardiac arrest (Fig. 1 and 2), including 6 newborns and 8 infants. Despite the resuscitation,  three (0.18%) children died during the procedures.

Child 1: a 2-day-old newborn (ASA V) qualified for aortic valvuloplasty. After induction of anaesthesia and exposure of the right internal carotid artery, the child developed sinus bradycardia with hypotension. Despite atropine and the continuous dopamine infusion, once the catheter was inserted into the left ventricle, sinus bradycardia with hypotension re-developed. Resuscitation was initiated and the planned procedure performed. The one-hour resuscitation did not restore haemodynamically efficient heart action and the child died. The pathomorphological findings showed fibroelastosis of the left atrium and left ventricle.

Child 2: a 2.5-year-old infant (ASA IV) with the Noonan syndrome, deficient body weight and congenital heart defect, sinus and suprasinus stenosis of the pulmonary artery, after the valvuloplasty at the age of 1 year was qualified for urgent re-valvuloplasty. Anaesthesia was induced and angiography as well as pressure measurements were performed. After the insertion of the catheter to the pulmonary artery trunk, the balloon was inflated twice. At the second inflation, the balloon ruptured and III degree A-V block occurred. Resuscitation was started. Since the block and haemodynamically inefficient heart action persisted, electrical stimulation of the heart was undertaken. The 1.5-hour resuscitation did not restore haemodynamically efficient heart work and the child died.

Child 3: a 7-year-old boy (ASA V) with congenital intricate heart defect, mitral valve atresia, atrial and ventricular septal defects, transposition of big vesels, after palliative therapy with symptoms of circulatory and multi-organ failure was qualified for angiography on day 3 after the Fontana procedure. An attempt to pass the catheter through the fenestration in the intracardiac tunnel resulted in sinus bradycardia, hypotension and cardiac arrest. Resuscitation was initiated, intravenous infusion of adrenaline instituted. Haemodynamically efficient heart action was restored for several minutes yet was followed by another cardiac arrest in the ventricular fibrillation mechanism. The 1.5-hour resuscitation failed.

DISCUSSION

Over the years, despite increased experiences of the team of cardiologists performing the procedures and anaesthesiologists taking care of patients as well as advances in medical techniques, the incidence rates of complications have not decreased. In relation to the number of procedures, the rates of complications are low – 1.78%; those of deaths amount to 0.18%. Our results are comparable with those reported by others [1, 2, 3]. According to some authors, the lack of improvement in safety of diagnostic and interventional procedures is associated with the medical personnel-related factors, organizational errors, unintentional technical errors and novel devices used [3, 4, 5]. However, such opinions were not confirmed in the present study. According to our findings, the factors increasing the risk of complications are associated with a patient, his/her age, type of heart defect, type of procedure, co-existing  circulatory failure, and selection for anaesthesia.

Children below 1 year of age – newborns and infants, predominate among patients with complications. In this age group, special technical difficulties in cardiac interventions and anaesthesia are encountered [3, 6]. The commonest procedures in this group are  emergency interventions, more difficult than diagnostic ones (Raskhind procedure, balloon dilation of the aortic valve stenosis) and the status of children is often critical. Patients are not fully diagnosed, additional health burdens or possible defects of other organs are unknown, therefore the risk of anaesthesia and interventional procedures is higher [2, 4].

Significant haemodynamic abnormalities most commonly occur during aortic and pulmonary valvuloplasty [7, 8] or during balloon dilatation of stenosis of systemic-pulmonary junctions in patients with complex heart defects after palliative procedures. Such interventions are associated with the highest mortality rates.

In cases of aortic valve stenosis, the defect occurrence is associated with age (newborns).  In children after palliative procedures, emergent interventions are performed, mainly due to dysfunction (thrombus, stenosis) of the systemic-pulmonary junction. The majority of these children had multiple cyanotic heart defects, underwent repeated procedures, and was disqualified for surgery in other cardiosurgical centres.

The incidences of complications during diagnostic and interventional procedures in our hospital are similar to those reported by other authors [6, 7]. Despite continuous efforts to improve their safety and reduce the number of complications, no substantial changes should be expected.  Severe complications are mostly related to an increasingly high number of neonates with critical, multiple heart defects, qualified for cardiac interventions during the prenatal period [9, 10].   

CONCLUSIONS

1. Diagnostic and interventional cardiac procedures in children with congenital heart defects are of low risk of peri-procedure complications.

2. The commonest complication is acute circulatory failure related to the technique of interventional procedures. Anaesthetic complications are rare.

3. The risk factors include age, pre-procedure severe status, type of heart defect and intervention.

REFERENCES

1.   Zahn EM, Dobrolet NC, Nykanen DG, Ojito J, Hannan RL, Burke RP: Interventional catheterization performed in the early postoperative period after congenital surgery in children. J Am Coll Cardiol 2004; 43: 1264-1269.

2.   Agnoletti G, Bonnet C, Boudjemline Y, Le Bihan C, Bonnet D, Sidi D, Bonhoeffer P: Complications of paediatric interventional catheterisation: an analysis of risk factors. Cardiol Young 2005; 15: 402-408.

3.   Odegard KC, DiNardo JA, Kussman BD, Shukla A, Harrington J, Casta A, McGowan FX Jr, Hickey PR, Bacha EA, Thiagarajan RR, Laussen PC: The frequency of anesthesia-related cardiac arrests in patients with congenital heart disease undergoing cardiac surgery. Anesth Analg 2007; 105, 301-303.

4.   Woloszczuk-Gebicka B: Problemy okresu okolooperacyjnego noworodków z wrodzona wada serca. Anaesthesiology Intensive Therapy 2001; 33; 17-21.

5.   Mehta R, Lee KJ, Chaturvedi R, Benson L: Complications of pediatric cardiac catheterization: a review in the current era. Catheter Cardiovasc Interv 2008; 72: 278-285.

6.   Simpson JM, Moore P,Teitel DF: Cardiac catheterization of low birth weight infants. Am J Cardiol 2001; 87; 1372-1377.

7.   Flori HR, Johnson LD, Hanley FL, Fineman JR: Transthoracic intracardiac catheters in pediatric patients recovering from congenital heart defect surgery: associated  complications and outcomes. Crit Care Med 2000; 28: 2997-3001.

8.   Rosales AM, Lock JE, Perry SB, Geggel RL: Interventional catheterization management of perioperative peripheral pulmonary stenosis; balloon angioplasty or endovascular stenting. Catheter Cardiovasc Interv 2002; 56; 272-277.

9.   Tay CL, Tan GM ,Ng SB: Critical incidents in pediatric anaesthesia ;an audit of 10anaesthetics in Singapore. Paediatr Anaesth 2001; 11; 711-718.

10. Welke KF, Shen I, Ungerleider RM: Current assessment of mortality rates in congenital cardiac surgery. Ann Thoracic Surg 2006; 82: 164-170.

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Address:

*Malgorzata Swiatnicka-Lucinska
Centrum Zdrowia Matki Polki
ul. Rzgowska 281/289, 93-338 Lódz
tel.: 0-4216 04, 0-608523
fax: 0-4214 19
e-mail: pl100@poczta.onet.pl

Received: 21.04.2009
Accepted: 08.06.2009