Blalock-Taussig shunt: Experience from the developing world

Predicting Factors for Mortality in Patients After the Modified Blalock-Taussig Shunt Procedure in Developing Countries: A Retrospective Study

Background

Blalock-Taussig (BT) is a palliative procedure that preserves blood circulation to the lungs and alleviates cyanosis in patients with congenital heart diseases and reduced pulmonary blood flow. BT shunt remains a routinely performed procedure in developing countries before definitive surgery. However, evidence on predictor factors of mortality after this procedure is still scarce in Indonesia. This study evaluated the predictive factors of mortality after the BT shunt procedure.

Methods

This retrospective study evaluated the medical record data of all postoperative BT shunt patients at Dr. Cipto Mangunkusumo Hospital, Jakarta, Indonesia, from 2016 to 2020. We performed univariate and multivariate analyses to identify the predictors of in-hospital mortality.

Results

The total subjects in this study were 197 children, 107 (54.3%) boys and 90 (45.7%) girls. The median values for age and body weight at the time of surgery were 20 months (11 days - 32 years) and 7.9 (2.7-42) kg. The most prevalent diagnosis was the Tetralogy of Fallot, found in 80 (40.6%) patients. In-hospital postoperative mortality was 20.8% (41 patients). Based on multivariate analysis, predictors associated with mortality were weight <4.25 kg (OR 20.9; 95% CI 7.4-59.0; p < 0.0001) and emergency procedures (OR 3.5; 95% CI 1.3-9.5; p = 0.016).

Conclusion

The mortality rate after BT shunt at PJT Rumah Sakit Cipto Mangunkusumo was 20.8%. Based on multivariate analysis, weight <4.25 kg and emergency procedures are two predictors of mortality in BT shunt.

Pulmonary artery growth after Modified Blalock-Taussig shunt: A single center experience

OBJECTIVE

This study evaluates growth of pulmonary artery (PA) between different age groups after Modified Blalock-Taussig shunt (MBTS) based on a single center experience.

METHODS

We retrospective analyzed outcomes of 90 patients undergoing MBTS in our institute from January 1, 2010 to May 1, 2018. Patients were divided into three groups: Group 1, ≦2 months, Group 2, >2 months, ≦24 wmonths, Group 3, >24 months. The outcome included PA growth, overall survival rates and postoperative complications.

RESULTS

23 patients were involved in Group 1, while 49 in Group 2 and 18 in Group 3. The diameter of the PA, McGoon ratio, Nakata index and the oxygen saturation increased significantly after MBTS. Compared to pre-MBTS, there was no statistically significant increase of McGoon ratio in Group 3 after performing MBTS, but it witnessed less secondary cardiac surgery rate compared with Group 2 (11.11% vs. 48.98%, P = 0.005). Cumulative survival rates of three groups were 60.53%, 85.70%, 94.40% at 1 year; 60.53%, 78.30%, 87.75% at 3 years and 60.53%, 78.30%, 87.75% at 5 years. Multivariable analysis showed diastolic blood pressure <30 mmHg [OR 14.14 (1.92-104.32), P = 0.009], cardiopulmonary bypass use [OR 16.79 (2.05-137.67), P = 0.009] and single ventricle anomaly [OR 8.80 (1.18-65.54), P = 0.034] were predictors of perioperative mortality.

CONCLUSION

MBTS in our institute is a conventional and effective procedure for growth of PA especially for patients younger than 24 months. Patients with biventricular anomaly, no cardiopulmonary bypass use in surgery and relatively high postoperative diastolic blood pressure will likely offer a good prognosis.

Effects of protocol-based management on the post-operative outcome after systemic to pulmonary shunt

Objectives

Systemic to pulmonary shunt (commonly known as Modified Blalock-Taussig shunt) is a palliative procedure in cyanotic heart diseases to overcome inadequate blood flow to the lungs. Based on the most recent risk stratification score, the mortality and morbidity of this procedure is still high especially in neonates and over-shunting patients. We developed and implemented protocol-based management in March 2013 to better standardize the management of these patients. The aim of this study is to evaluate the effects of applying this protocol-based management in our center.

Methods

We conducted a retrospective cohort study through chart review analysis.We included all children who underwent MBTS from January 2000 till December 2015. We compared the early postoperative outcome of patients operated after the protocol-based management implementation (March 2013 till December 2015) (protocol group) with patients operated before implementing the MBTS protocoled management (control group).

Results

197 patients underwent MBTS from January 2000 till December 2015. Of the 197 patients, 25 patients were in the protocol group and 172 patients were in the control group. There was a significant improvement in the postoperative course and less morbidity after protocoled management implementation as reflected in ventilation time, reintubation rate, inotropic support duration, intensive care unit ICU stay and significantly lower postoperative complications in the protocol group. Mortality of the control group versus protocol group (19.3% VS 8%) with Standardized Mortality Ratio (SMR) dropped from 2.27 before protocoled management to 0.94 after protocoled management (protocol group).

Conclusion

The study suggests that protocoled management of patients with MBTS can improve the postoperative course and early outcome.

Risk Factors for Thrombosis, Overshunting and Death in Infants after Modified Blalock-Taussig Shunt

BACKGROUND

The Modified Blalock-Taussig shunt procedure can provide increased flow of blood to the lungs for babies born with certain congenital heart defects. We evaluated 44 subjects under 2 years of age who had a Modified Blalock-Taussig shunt (MBTS) procedure performed from 2009-2013, to investigate risk factors for thrombosis, overshunting and death.

METHODS

The study subjects included in our investigation were severely cyanotic newborns with pulmonary stenosis or atresia and duct dependent circulation, and infants having Tetralogy of Fallot with small pulmonary arteries who underwent a MBTS procedure in our facility from 2009-2013. We duly noted patient preoperative characteristics such as hemoglobin, hematocrit, mean platelet volume, prothrombin time and partial thromboplastin time. Our study investigated the risk factors for post-operative overcirculation, thrombosis and death.

RESULTS

The age and weight of patients in our study at the time of procedure ranged from 1 day to 20 months old (median 12 days), and 2.4 kg to 12 kg (mean 4.6 kg), respectively. A total of 8 patients died following surgery, and. 4 (9.1%) had shunt thrombosis, of which one died during shunt revision. Partial thromboplastin time was 28.7 seconds in patients with thrombosis, and 35 in all other patients (p = 0.04). Overcirculation was detected in 5 patients; shunt size/body weight was 1.25 in patients who had overcirculation, and 1.06 in all other patients.

CONCLUSIONS

It is important to assess risk factors associated with the MBTS operation. The results of our study suggest that a preoperative low aPTT value may be an indicator for thrombosis in infants who have undergone MBTS surgery.

Barriers to accessing surgical care in Pakistan: healthcare barrier model and quantitative systematic review

Inadequate access to surgical services results in increased morbidity and mortality from a spectrum of conditions in Pakistan. We employed a modification of Andersen's model of health services utilization and developed a 'Healthcare Barrier Model,' to characterize the barriers to accessing health care in developing countries, using surgical care in Pakistan as a case study. We performed a literature search from MEDLINE, EMBASE, CINAHL, SCOPUS, Global Health Database, and Cochrane Central Register of Controlled Trials, and selected 64 of 3113 references for analysis. Patient-related variables included age (elderly), gender (female), preferential use of alternative health providers (Hakeem, traditional healers, others), personal perceptions regarding disease and potential for treatment, poverty, personal expenses for healthcare, lack of social support, geographic constraints to accessing a health facility, and compromised general health status as it relates to the development of surgical disease. Environmental barriers include deficiencies in governance, the burden of displaced or refugee populations, and aspects of the medicolegal system, which impact treatment and referral. Barriers relating to the health system include deficiencies in capacity (infrastructure, physical resources, human resources) and organization, and inadequate monitoring. Provider-related barriers include deficiencies in knowledge and skills (and ongoing educational opportunities), delays in referral, deficient communication, and deficient numbers of female health providers for female patients. The Healthcare Barrier model addresses this broad spectrum of barriers and is designed to help formulate a framework of healthcare barriers. To overcome these barriers will require a multidisciplinary, multisectoral effort aimed at strengthening the health system.