Table 1 Sample characteristics

Number of Patients

249

Site n(%)

   Stollery Children's Hospital

55 (22.1%)

   Hospital for Sick Children

194 (77.9%)

Length of hospital stay in days (Mean ± SD, Range)

11 (± 21, 2–305)

Age in years (Mean ± SD, Range)

7.6 ± 4.4, 0.3–-16.8

Age in Quartiles n(%)

   0 to <4 years

65 (26.1%)

   4 to <7 years

61 (24.5%)

   7 to < 12 years

75 (30.1%)

   12 to <17 years

48 (19.3%)

Male: Female (Ratio %)

128 (51.4%):121 (48.6%)

Surgery n(%)

   Brain Tumour

153 (61.4%)

   Chiari I Malformation

81 (32.5%)

   Other

15 (6.0%)

Chiari II Malformation

7 (2.8%)

Vascular Malformation

4 (1.6%)

Cyst or Aspiration of Pus

4 (1.6%)

Presenting with vomiting n(%)

115 (46.2%)

Preoperative Dexamethasone n(%)¹

136 (54.6%)

Intraoperative Ondansetron

117 (47.0%)

   Without Dexamethasone

47 (18.9%)

Intraoperative Dexamethasone

131 (52.6%)

   Without Ondansetron

61 (24.5%)

Intraoperative Ondansetron and Dexamethasone

70 (28.1%)

No intraoperative anti-emetic

71 (28.5%)

Length of surgery in hours (Mean ± SD, Range)

5:01 ± 2:10 (1:39–17:56)

Length of anaesthesia in hours (Mean ± SD, Range)

6:22 ± 2:20 (2:05–20:15)

Type of volatile anaesthetic n(%)

   Isoflurane

126 (50.6%)

   Desflurane

46 (18.5%)

   Isoflurane + Sevoflurane

32 (12.9%)

   Sevoflurane

22 (8.8%)

   Isoflurane + Desflurane

8 (3.2%)

   Sevoflurane + Desflurane

2 (0.8%)

   Not recorded/not legible

13 (5.2%)

Use of Nitrous Oxide**

7 (2.8%)

Received Postoperative Anti-emetic (%)

199 (79.9%)

Opioid administration initiated by the first 24 hours (%)

228 (91.6%)