Comparison of non-assisted versus head and tail rope-assisted recovery after emergency abdominal surgery in horses

Abstract

The objective of this study was to compare anaesthetic recoveries without assistance (group NA) to a head and tail rope-assisted technique (group A) after emergency abdominal surgery in horses. Additionally, possible risk factors for the quality of recovery (S: safe, NS: non-safe) were investigated and possible complications associated to the head and tail rope technique recorded. For that purpose 200 anaesthetic protocols (100NA, 100A) from horses that all received a standardised medetomidine-isoflurane balanced anaesthesia regime and medetomidine in combination with morphine for recovery were analysed retrospectively. No significant difference regarding recovery score was detected between NA and A horses. Fatalitalities (3/100 in each group) were similarly distributed between groups. However, in group NA only one horse died because of trauma during recovery. The other two horses died before attempting to stand up. All 3 horses that died in group A were euthanized because of trauma. Hypoxemia (defined as arterial oxygen partial pressure <60mmHg) during anaesthesia was a risk factor for non-safe recoveries. No influence was detected for age, weight, duration of general anaesthesia, reason of colic surgery, recovery technique (A, NA), hypotension during anaesthesia, time in lateral recumbency, time in sternal recumbency and time until standing. Several technical complications (material fail, twisting of ropes, halters slipping off and loss of ropes) were observed using the head and tail ropes, probably being partially responsible for the unexpectedly high number of dangerous and fatal recoveries observed in group A. The present study could not demonstrate that the head and tail rope technique can reduce fatalities or improve anaesthetic recovery scores after emergency abdominal surgery in horses. Hypoxemia during general anaesthesia increases the risk of non-safe recovery