Anaesthesia and recently vaccinated children

[Myocarditis exacerbation in a child undergoing inguinal herniopasty after viral infection]

INTRODUCTION

Immunosuppressive effects of general anaesthesia and surgery could have unexpected consequences in a child with recent infection. The incidence of myocarditis in childhood is unknown.

CASE OUTLINE

During general anaesthesia for inguinal hernia repair, a seven-year-old boy suddenly developed heart failure. Clinical presentation included hypotension, pulmonary oedema, drop in haemoglobin oxygen saturation, ST segment elevation and premature ventricular contractions. Haemodynamic stability and adequate oxygenation were achieved with dopamine and furosemide. Preoperative history, physical examination and complete blood count were unremarkable. Moderate cardiomegaly and pulmonary oedema were present on chest radiography. Diminished left ventricular contractility found on echocardiography increased troponin I and CK-MB levels suggested myocardial injury. Increased C-reactive protein with lymphocytosis suggested inflammation as its cause. Parents failed to report rubella 10 days before the operation. A clinical diagnosis of myocarditis as a complication of rubella was based on increased titer of IgM to rubella. With intravenous immunoglobulin, corticosteroids and symptomatic treatment for heart failure, his condition improved and ejection fraction reached 68% one month after operation.

CONCLUSION

In future, we need protocols with instructions for paediatric patients undergoing elective surgery and anaesthesia after viral infections.

Influence of anesthesia on immune responses and its effect on vaccination in children: review of evidence

Anesthesia and surgery exert immunomodulatory effects and some authors argue that they may exert additive or synergistic influences on vaccine efficacy and safety. Alternatively, inflammatory responses and fever elicited by vaccines may interfere with the postoperative course. There is a lack of consensus approach among anesthesiologists to the theoretical risk of anesthesia and vaccination. Few studies have assessed the influence of anesthesia and surgery on pediatric vaccine responses. We have undertaken an extensive review of articles published in English between 1970 and 2006 meeting the criteria: measurement of immune parameters following general anesthesia in children. By searching the major medical databases (OVID Medline, PubMed, ISI Web of Science) and references cited in the articles themselves, among 277 articles obtained none examined directly the influence of anesthesia/surgery on vaccine responses. Only 16 original reports assessed the influence of several anesthetic agents on various markers of immunity including lymphocyte numbers and functions. These results are reinterpreted here in view of our current understanding of the immune mechanisms underlying vaccine efficacy and adverse events. We conclude that the immunomodulatory influence of anesthesia during elective surgery is both minor and transient (around 48 h) and that the current evidence does not provide any contraindication to the immunization of healthy children scheduled for elective surgery. However, respecting a minimal delay of 2 days (inactivated vaccines) or 14-21 days (live attenuated viral vaccines) between immunization and anesthesia may be useful to avoid the risk of misinterpretation of vaccine-driven adverse events as postoperative complications.

Immunization and anesthesia - an international survey

BACKGROUND

There is no direct evidence of any major interaction between immunization and commonly used anesthetic agents and techniques in children, but it is possible that immunosuppression caused by anesthesia and surgery may lead to decreased vaccine effectiveness or an increased risk of complications. In addition, diagnostic difficulty may arise if a recently immunized child suffers from postoperative pyrexia or malaise.

AIM

The aim of this study was to ascertain anesthetists' attitudes and practices regarding anesthesia and immunization.

METHODS

We conducted an international survey of members of the Association of Paediatric Anaesthetists of Great Britain and Ireland (APAGBI) and the Society for Paediatric Anaesthesia of New Zealand and Australia (SPANZA).

RESULTS

Two hundred and ninety-six (52.1%) APAGBI and 86 (49.4%) SPANZA responses were analyzed. There was no consensus of approach to this theoretical risk among respondents. In total, 60% of respondents would anesthetize a child for elective surgery within 1 week of receiving a live attenuated vaccine, but 40% would not. Few hospitals have formal policies on this issue and government guidance is based on a lack of evidence for adverse events rather than positive evidence of safety.

CONCLUSIONS

There is a theoretical risk associated with anesthesia and surgery in recently immunized children. An international postal survey failed to find a consensus to this risk among pediatric anesthetists. From a risk management perspective, a review of the available evidence suggests that it would be prudent to adopt a cautious approach where the timing of elective surgery is discretionary. We therefore recommend that elective surgery and anesthesia should be postponed for 1 week after inactive vaccination and 3 weeks after live attenuated vaccination in children.