Meconium aspiration syndrome MAS

49 A sub-group analysis was done Tables 31c and 31d for ventilated MAS with no HIE n=636 versus mildmod HIE n=106. There was no significant difference between the 2 groups for morbidity and mortality. The mortality of ventilated MAS was 9 in these 2 groups with a median age of death of ≤2 days. The incidence of pneumothorax was 10.5. The median duration of ventilation for survivors in the ‘no HIE’ group was 8 days IQR 6,13 and 6 days 4,7 for mildmod HIE group. A logistic regression was performed Table 31e for risk of mortality in the ‘no HIE’ group. The factors associated with mortality were birthweight2500g p = 0.001, pneumothorax and PPHN both p 0.001. Our incidence of ventilated MAS and mortality rate was higher than Australia New Zealand 0.43 per 1,000 LB and 2.5 mortality – Dargaville Ped 2006. The absence of grades of MAS prevents further subgroup analysis Table 31c – The Characteristics of Ventilated MAS No. Characteristics No HIE, n1 = 636 MildMod HIE, n2=106 p-value 1 LSCS, n 315 50 51 48 0.787 2 Ventilation, n Conventional alone Conventional + HFOV HFOV alone 265 42 52 8 9 1 49 46 8 8 5 5 0.378 0.826 0.021 3 Given iNO 18 3 3 3 1.000 4 MAS + PPHN, n 154 24 26 25 0.944 5 Confirmed sepsis, n 37 6 4 4 0.394 Table 31d – The Outcomes of Ventilated MAS No. Characteristics No HIE, n1 = 636 MildMod HIE, n2=106 p-value 1 Pneumothorax, n 68 11 10 9 0.696 2 Days on respiratory support for ALL babies Conventional ± HFOV – Median IQR 8 4.5,12 5 2.5,6.5 0.079 3 Days on respiratory support for SURVIVORS Conventional ± HFOV – Median IQR 8 6,13 6 4,7 0.086 4 Days in hospital for ALL – median IQR 7 5,12 8 5,11 0.511 5 Days in hospital for SURVIVORS only – median IQR 7 5,12.5 8.5 6,12 0.335 6 Number and who died 56 9 10 9 0.833 7 For those who died, days of life at the time of death – median IQR 2 1,6 1.5 1,5 0.763 Table 31e - Risk factors selected for Mortalityin Ventilated MAS with No HIE, N=636 Logistic Regression No. Parameter Alive, n1=580 Died, n2=56 p-value 1 Birthweight, n 2500g g 62 11 518 89 13 23 43 77 0.001 2 Pneumothorax, n 49 8 19 34 0.001 50 3 PPHN, n 116 20 38 68 0.001 4 Confirmed Sepsis, n 336 47 0.102 3.7.1.6 Pneumothorax PTX Of the 11,219 infants recruited into the MNNR in the year 2008, 510 4.5 developed penumothorax. This was similar to previous years. The median birth weight of these infants was 2300 g IQR: 1300, 2960 and their median gestational age was 36 weeks 30, 40. Majority of them were inborn 82. Males constituted 59. Their ethnic distribution was : Malays 67, Chinese 8, Indians 6 and others 19. Majority of them were delivered either by SVD 50 or LSCS 45. Majority 87 of these infants received conventional ventilator support and 22 received high frequency oscillatory ventilation. Without data on the age of pneumothorax and the temporal relationship with these ventilator support modes, it is not possible to determine whether the ventilation caused the pneumothorax or that the various modes of ventilation was used to support the infants following development of pneumothorax. The mortality rate among these infants was very high as 42 of them died. 3.7.2 Hypoxic ischaemic encephalopathy HIE Of the 73961 infants admitted to the 32 participating NICUs of the MNNR in 2008, 893 1.2 were diagnosed to have hypoxic ischeamic encephalopathy HIE. These 893 infants formed 8.0 of the 11,219 infants recruited in the MNNR. 70 of the infants with HIE were Malays. 59 were males. 82 of them were inborn. 49 of the infants were delivered by SVD, 35 by LSCS and the remainder by other methods. At birth in the labour rooms, 12 of infants with HIE required cardiac massage. The median birth weight of these infants was 3000 g IQR: 2695, 3300 and their median gestation was 39 weeks IQR: 38, 40. 26.7 of the 893 infants with HIE were of severe type. The remaining infants with HIE were either of mild or moderate types. Death occurred in 23 of the infants. Mortality was much higher in infants with severe HIE as 68 of them died when compared with 6 of infants with mild or moderate HIE. In summary, rates of HIE and its mortality rates have not changed much when compared with 2007. 3.7.3 Causes of death The frequency and mortality associated with the major morbidities were as follows: 51 Figure 32. Deaths associated with major morbidities The most common morbidities among the babies in the study was Respiratory Distress Syndrome RDS that was 5012 babies followed by infection 5215 babies,pneumonia 2142 babies and major congenital anomalies 1854 babies. Mortality were high among babies with severe hypoxic ischaemic encephalopathy, pneumothorax, PPHN and major congenital anomalies which were 69, 42, 42 and 40 respectively. In terms of numbers, deaths were associated with infection and RDS or prematurity,and major congenital malformations. 3.7.4 Intraventricular haemorrhage 3.7.4.1 The rates of cranial ultrasound in 2008 Ultrasound imaging of the head of very preterm babies is performed to detect both intraventricular haemorrhage IVH and the formation of cysts and ventricular dilatation hydrocephalus. An initial cranial ultrasound CUS is generally performed during the first week of life to detect signs of IVH. Grade 1 and 2 are milder grades and generally do not affect the outcome adversely, while Grade 3 and 4 are not only associated with early morbidity and mortality but are also markers of possible later disabilities. 1000 2000 3000 4000 5000 6000 N u m b e r o f b a b ie s Type of morbidity Fig. 32 Deaths associated with major morbidities Dead Alive 52 Figure33. Cranial Ultrasound CUS of brain in babies with birthweight 1500g, Years 2004- 2008

3.7.4.2 Severity of intraventricular haemorrhage

Among the babies in this birth weight group who underwent CUS, 339 13.6 had Grade 3 or 4 IVH. This showed an increment compared to the last 4 years 11.6, 12.1 , 11.5 in 2007, 2006, 2005 and 2004 respectively. The combined mortality rate from Grade 3 and 4 IVH was 63; the highest from the last 3 years 51.7, 54.6, 60.3 and 58 in 2007, 2006, 2005 and 2004 respectively Table 33. This slight increment in morbidity may indicate that more centres were more aggressive in the management of smaller premature babies – and this may be a reflection of the ‘learning curve’ in managing these babies. The increment in mortality in babies with severe IVH could indicate a more conservative approach once the babies developed severe IVH. Nevertheless, centres that showed increment in the rate of severe IVH or mortality rate should probably review their own protocols in the early management of ELBW babies and infection control – as pictured in this data, once a baby developed grade 3 4 IVH, their mortality increased to more than 60. See Table 42 If we interpret the data from a different angle, 37 124 babies from this cohort survived to discharged with a high likelihood of severe neuro-developmental disabilities. This in fact is a valuable data in the national planning of support for this group of babies later on. In figure 34, the percentages of babies with grade 2 to grade 4 IVH are compared between 2008 and the previous years. 1660 2243 2413 2549 2492 1131 1111 1172 1102 1154 10 20 30 40 50 60 70 80 90 100 2004 2005 2006 2007 2008 p e rc e n ta g e o f b a b ie s sc a n n e d Year Fig. 33: Cerebral Ultrasound in babies birthweight 501-1500 g, year 2004-2008 No CUS CUS 53 Figure 34. Percentage of babies screened according to IVH grade, and year Figure 35. Percentages of grades of IVH among screened VLBW babies 500 1000 1500 2000 2500 3000 CUS done grade 2 grade 3 grade 4 N u m b e r o f b a b ie s Fig. 34: Number of babies screened according to IVH grade and year 2004 2005 2006 2007 2008 2 4 6 8 10 12 14 2004 2005 2006 2007 2008 P e rc e n ta g e o f b a b ie s Year Fig. 35: Percentage of grades of IVH among screened VLBW babies, 2004-2008 grade 2 grade 3 grade 4