In this study, we retrospectively performed a review of medical records of all patients who underwent scoliosis surgery between January 2018 and January 2021. A total of 165 patients were included; (64.2% were female and the mean age was 21.6 ± 16.7 years). The most frequent aetiologies of scoliosis were idiopathic, congenital, degenerative and neuromuscular. In 48 patients who required Intensive Care Unit (ICU) stay, the rate of comorbidity was 75% (n = 36); lung disease was present in 54% (n = 26) of cases and restrictive lung disease was present in 47.9% of cases (n = 23), which were significantly higher than those who did not require ICU stay (p < 0.001). The proportion of patients with neuromuscular problems was 45.8% (n = 22) (p = 0.004) while those with epilepsy was 16.7% (n = 8) (p = 0.027). The proportion of patients with neuromuscular scoliosis was 25% (n = 12), the median number of fused vertebrae (fusion level) was 15, and the proportion of American Society of Anaesthesiologists (ASA) III patients was 54.2%(n = 26) (all p < 0.001). The median surgical duration was 307.5 minutes (p = 0.006) and the proportion of patients which received blood transfusion was 91.7% (n = 44) (p = 0.002). The pre- and post-operative haemoglobin (Hb) levels, and the post-operative arteriel blood gases (ABG) potential of hydrogen (pH) and lactate levels of patients, who needed ICU were significantly different from those who did not require the ICU (p = 0.043, p = 0.039, p < 0.001 and p = 0.037). In conclusion, a presence of restrictive lung disease, epilepsy, neuromuscular scoliosis, a high fusion level, a need for blood transfusion, long surgical duration, low Hb and pH values, and high lactate levels were found as the predictors of ICU admission.