Common Arterial Trunk Repair at the Red Cross War Memorial Hospital, Cape Town: A 20-Year Review of Surgical Practice and Outcomes.

BACKGROUND: This study describes the 20-year experience of managing common arterial trunk (CAT) in a low-and-middle-income country and compares the early and medium-term outcomes following the transition from conduit to nonconduit repair at the Red Cross War Memorial Children's Hospital. METHODS: Single-center retrospective study of consecutive patients aged less than 18 years who underwent repair of CAT from January 1999 to December 2018 at the Red Cross War Memorial Children's Hospital. Patients with interrupted aortic arch or previous pulmonary artery banding were excluded. RESULTS: Fifty-four patients had CAT repair during the study period. Thirty-four (63.0%) patients had a conduit repair, and 20 (37.0%) patients had a nonconduit repair. There were two intraoperative deaths. Thirty-day in-hospital mortality was 22.2% (12/54). Overall, in-hospital mortality was 29.6% (16/54). Eight (21.1%) late mortalities were observed. The actuarial survival for the conduit group was 77.5%, 53.4%, and 44.5% at 6, 12, and 27 months, respectively, and the nonconduit group was 58.6% at six months. The overall freedom from reoperation between the conduit group and nonconduit group was 66.2% versus 86.5%, 66.2% versus 76.9%, and 29.8% versus 64.1% at 1, 2, and 8 years, respectively. CONCLUSIONS: The outcomes following the transition to nonconduit repair for CAT in a low- and middle-income setting appear to be encouraging. There was no difference in mortality between conduit and nonconduit repairs, and importantly the results suggest a trend toward lower reintervention rates.

Ventilator-associated pneumonia in PICU - how are we doing?

Background: Ventilator-associated pneumonia (VAP) is a common hospital-acquired infection in children, leading to an increase in morbidity and mortality. A previous study in 2013 showed that VAP rates decreased dramatically after implementation of a VAP bundle and appointing a VAP coordinator. As part of a 'Plan, Do, Study, Act' cycle, it was necessary to evaluate the efficacy of these interventions. Objectives: To evaluate the VAP rate in the paediatric intensive care unit (PICU) over 2 years (2017 - 2018), and to describe the causative organisms and antibiotic sensitivity/resistance patterns during this period. Methods: This was a retrospective, descriptive study using the existing PICU VAP database as well as clinical folders. Results: Over the 2 years, 31 VAP cases were identified. The VAP rate for 2017 was 4.0/1 000 ventilator days and 5.4/1 000 ventilator days for 2018. Compliance with the VAP bundle was 68% in 2017 and 70% in 2018. The median (interquartile range (IQR)) duration of ventilation in 2017 was 9 (6 -12) days and 15 (11 - 28) days in 2018. The median (IQR) length of PICU stay in 2017 was 11 (8 - 22) days and 25 (17 - 37) days in 2018. The most common cultured organism was an extended-spectrum beta-lactamase (ESBL) Klebsiella pneumoniae sensitive to amikacin and carbapenems. Conclusion: Our VAP rate has not decreased since 2013. It is imperative that we improve compliance with the VAP bundle, in order to reduce VAP rates. K. pneumoniae and Pseudomonas aeruginosa were the most common organisms causing VAPs and empiric use of piptazobactam and amikacin is still appropriate. Contributions of the study: This study highlights the need for ongoing evaluation of quality improvement initiatives in PICU, considering that VAP rates remained largely unchanged from 2013 to 2018.

Risk factors and outcomes of extubation failure in a South African tertiary paediatric intensive care unit.

Background: Extubation failure contributes to poor outcome of mechanically ventilated children, yet the prevalence and risk factors have been poorly studied in South African (SA) children. Objectives: To determine the prevalence, risk factors and outcomes of extubation failure in an SA paediatric intensive care unit (PICU). Methods: This was a prospective, observational study of all mechanically ventilated children admitted to a tertiary PICU in Cape Town, SA. Extubation failure was defined as requiring re-intubation within 48 hours of planned extubation. Results: There were 219 episodes of mechanical ventilation in 204 children (median (interquartile range (IQR)) age 8 (1.6 - 44.4) months). Twenty-one of 184 (11.4%) planned extubations (95% confidence interval (CI) 7.2% - 16.9%) failed. Emergency cardiac admissions (adjusted odds ratio (aOR) 7.58 (95% CI 1.90 - 30.29), dysmorphology (aOR 4.90; 95% CI 1.49 - 16.14), prematurity (aOR 4.39; 95% CI 1.24 - 15.57), and ventilation ≥48 hours (aOR 6.42 (95% CI 1.57 - 26.22) were associated with extubation failure. Children who failed extubation had longer durations of ventilation (231 hours (146.0 - 341.0) v. 53 hours (21.7 - 123.0); p<0.0001); longer duration of PICU (15 (9 - 20) days v. 5 (2 - 9) days; p<0.0001) and hospital length of stay (32 (21 - 53) days v. 15 (8 - 27) days; p=0.009); and higher 30-day mortality (28.6% v. 6.7%; p=0.001) than successfully extubated children. Conclusion: Extubation failure was associated with significant morbidity and mortality in our setting. Risk factors for extubation failure identified in our context were similar to those reported in other settings. Contributions of the study: This study provides novel data on the prevalence, risk factors and outcomes associated with extubation failure in a single-centre South African PICU. The results of this study may help identify high-risk groups for extubation failure within our local context, and forms a basis for practice improvement initiatives aimed at decreasing extubation failure rates and improving outcomes.

A review of the use of inhaled nitric oxide in the PICU at Red Cross War Memorial Children's Hospital, 2011-2015: A retrospective cohort study.

Background: Inhaled nitric oxide (iNO) functions as a selective pulmonary vasodilator. It is an expensive treatment that is often employed as rescue therapy for refractory hypoxaemia in acute respiratory distress syndrome (ARDS) and pulmonary hypertension (PHT) following cardiac surgery. Objectives: To describe the use of iNO and the cost of treatment in our paediatric intensive care unit (PICU). Methods: A retrospective descriptive study of all patients treated with iNO in the PICU at Red Cross War Memorial Children's Hospital (RCWMCH) from 2011 - 2015. Results: We treated 140 patients with iNO, 82 for PHT following cardiac surgery, 53 for ARDS and 5 for persistent pulmonary hypertension of the newborn (PPHN). A response to treatment was observed in 64% of the cohort as a whole, 80% of those with PPHN, 67% of those with PHT post-cardiac surgery, and 64% of those with ARDS. A longer duration of PICU and hospital admission, and higher in-hospital mortality (53%), was seen in the group with ARDS, in particular those with adenoviral infection (63%), when compared with patients treated for PHT post-cardiac surgery (18%) and for PPHN (20%). The total cost of treatment with iNO was ZAR1 441 376 for the 5-year period studied. There are no protocols guiding the use of iNO in our unit, and it was found that response to treatment was not being objectively measured and documented, and that practice varied between clinicians. Conclusion: Considering the cost of treatment and lack of evidence showing improved outcomes with iNO therapy, its continued use in our resource-limited setting should be guided by protocol. Contributions of the study: There is a paucity of data regarding the indications for use, and outcomes of patients treated with iNO in resource-limited settings. We did not find evidence of improved outcomes in patients treated with iNO despite the high costs of the therapy. Protocols should be developed to guide the use of iNO in resource-limited settings.

Hyperchloraemic metabolic acidosis following open cardiac surgery.

AIMS: To describe acid-base derangements in children following open cardiac surgery on cardiopulmonary bypass (CPB), using the Fencl-Stewart strong ion approach. METHODS: Prospective observational study set in the paediatric intensive care unit (PICU) of a university children's hospital. Arterial blood gas parameters, serum electrolytes, strong ion difference, strong ion gap (SIG), and partitioned base excess (BE) were measured and calculated on admission to PICU. RESULTS: A total of 97 children, median age 57 months (range 0.03-166), median weight 14 kg (range 2.1-50), were studied. Median CPB time was 80 minutes (range 17-232). Predicted mortality was 2% and there was a single non-survivor. These children showed mild metabolic acidosis (median standard bicarbonate 20.1 mmol/l, BE -5.1 mEq/l) characterised by hyperchloraemia (median corrected Cl 113 mmol/l), and hypoalbuminaemia (median albumin 30 g/l), but no significant excess unmeasured anions or cations (median SIG 0.7 mEq/l). The major determinants of the net BE were the chloride and albumin components (chloride effect -4.8 mEq/l, albumin effect +3.4 mEq/l). Metabolic acidosis occurred in 72 children (74%) but was not associated with increased morbidity. Hyperchloraemia was a causative factor in 53 children (74%) with metabolic acidosis. Three (4%) hyperchloraemic children required adrenaline for inotropic support, compared to eight children (28%) without hyperchloraemia. Hypoalbuminaemia was associated with longer duration of inotropic support and PICU stay. CONCLUSIONS: In these children with low mortality following open cardiac surgery, hypoalbuminaemia and hyperchloraemia were the predominant acid-base abnormalities. Hyperchloraemia was associated with reduced requirement for adrenaline therapy. It is suggested that hyperchloraemic metabolic acidosis is a benign phenomenon that should not prompt escalation of haemodynamic support. By contrast, hypoalbuminaemia, an alkalinising force, was associated with prolonged requirement for intensive care.

Symptomatic HIV infection in infancy--clinical and laboratory markers of infection.

OBJECTIVE: To investigate the usefulness of immunological tests in the diagnosis of HIV infection in young symptomatic children (< 15 months of age). DESIGN: Tests were evaluated in HIV-infected (HIV antibody- and PCR-positive) patients and non-infected individuals. SETTING: Hospitalised patients in a referral centre (Red Cross War Memorial Children's Hospital, Cape Town). PATIENTS: All admissions under 15 months of age who had HIV antibody requested were eligible, provided there was sufficient serum (150 microliter) for further study. Overall, there were 201 symptomatic cases and 49 healthy controls. Twenty of the symptomatic cases were HIV antibody-positive and 19 of these were HIV-infected on the basis of a positive PCR for HIV viral product. RESULTS: Of the tests we evaluated (total IgG, IgM, IgA and rheumatoid factors of the same classes), raised total IgG level (cut-off 18 g/I or above) was the most useful. We used a commercial radial immunodiffusion plate which was found to have excellent reproducibility (inter-assay coefficient of variation 3.2%). The test detected 16 of 19 infected infants (sensitivity 84%, negative predictive value 98%). With the exception of the finding of oral thrush (odds ratio 7; P < 0.001), the clinical signs at presentation did not distinguish those who were HIV antibody-positive from those who were negative. CONCLUSIONS: In our study of hospital admissions, the finding of elevated IgG and HIV antibody was diagnostic of HIV infection. (The positive predictive value of the combination was 100%.) Likewise, the presence of raised IgG levels and oral candidosis had a high specificity for HIV infection (98%) but the sensitivity was low (37%). Measurement of total IgG levels by radial immunodiffusion is simple, relatively inexpensive (< 10% of the cost of PCR), helpful in diagnosing HIV infection in symptomatic infants and able to be performed in areas with minimal laboratory back-up.