Evaluation of the efficacy and safety for use of two sedation and analgesia protocols to facilitate assisted ventilation of healthy dogs

Michael R. Ethier Department of Clinical Studies, Ontario Veterinary College, University of Guelph, Guelph, ON N1H 2W1, Canada.

Search for other papers by Michael R. Ethier in
Current site
Google Scholar
PubMed
Close
 DVM
,
Karol A. Mathews Department of Clinical Studies, Ontario Veterinary College, University of Guelph, Guelph, ON N1H 2W1, Canada.

Search for other papers by Karol A. Mathews in
Current site
Google Scholar
PubMed
Close
 DVM, DVSc
,
Alexander Valverde Department of Clinical Studies, Ontario Veterinary College, University of Guelph, Guelph, ON N1H 2W1, Canada.

Search for other papers by Alexander Valverde in
Current site
Google Scholar
PubMed
Close
 DVM, DVSc
,
Carolyn Kerr Department of Clinical Studies, Ontario Veterinary College, University of Guelph, Guelph, ON N1H 2W1, Canada.

Search for other papers by Carolyn Kerr in
Current site
Google Scholar
PubMed
Close
 DVM, PhD
,
Alexa M. Bersenas Department of Clinical Studies, Ontario Veterinary College, University of Guelph, Guelph, ON N1H 2W1, Canada.

Search for other papers by Alexa M. Bersenas in
Current site
Google Scholar
PubMed
Close
 DVM, MS
,
Stephanie G. Nykamp Department of Clinical Studies, Ontario Veterinary College, University of Guelph, Guelph, ON N1H 2W1, Canada.

Search for other papers by Stephanie G. Nykamp in
Current site
Google Scholar
PubMed
Close
 DVM
, and
Clive Davis Critical Care Medicine, Hamilton General Hospital, McMaster University, Hamilton, ON L8S 4L8, Canada.

Search for other papers by Clive Davis in
Current site
Google Scholar
PubMed
Close
 MD

Abstract

Objective—To determine the effectiveness and safety of 2 sedative-analgesic protocols to facilitate assisted ventilation in healthy dogs.

Animals—12 healthy dogs.

Procedures—Dogs were randomly assigned to 2 groups. Mean dosages for protocol 1 were diazepam (0.5 mg/kg/h [n = 3 dogs]) or midazolam (0.5 mg/kg/h [3]), morphine (0.6 mg/kg/h [6]), and medetomidine (1.0 μg/kg/h [6]). Mean dosages for protocol 2 were diazepam (0.5 mg/kg/h [n = 3]) or midazolam (0.5 mg/kg/h [3]), fentanyl (18 μg/kg/h [6]), and propofol (2.5 mg/kg/h [6]). Each dog received the drugs for 24 consecutive hours. All dogs were mechanically ventilated with adjustments in minute volume to maintain normocapnia and normoxemia. Cardiorespiratory variables were recorded. A numeric comfort score was assigned hourly to assess efficacy. Mouth care, position change, and physiotherapy were performed every 6 hours. Urine output was measured every 4 hours.

Results—Use of both protocols maintained dogs within optimal comfort ranges > 85% of the time. The first dog in each group was excluded from the study. Significant decreases in heart rate, oxygen consumption, and oxygen extraction ratio were evident for protocol 1. Cardiac index values in ventilated dogs were lower than values reported for healthy unsedated dogs. Oxygen delivery, lactate concentration, and arterial base excess remained within reference ranges for both protocols.

Conclusions and Clinical Relevance—Use of both protocols was effective for facilitating mechanical ventilation. A reduction in cardiac index was detected for both protocols as a result of bradycardia. However, oxygen delivery and global tissue perfusion were not negatively affected.

Abstract

Objective—To determine the effectiveness and safety of 2 sedative-analgesic protocols to facilitate assisted ventilation in healthy dogs.

Animals—12 healthy dogs.

Procedures—Dogs were randomly assigned to 2 groups. Mean dosages for protocol 1 were diazepam (0.5 mg/kg/h [n = 3 dogs]) or midazolam (0.5 mg/kg/h [3]), morphine (0.6 mg/kg/h [6]), and medetomidine (1.0 μg/kg/h [6]). Mean dosages for protocol 2 were diazepam (0.5 mg/kg/h [n = 3]) or midazolam (0.5 mg/kg/h [3]), fentanyl (18 μg/kg/h [6]), and propofol (2.5 mg/kg/h [6]). Each dog received the drugs for 24 consecutive hours. All dogs were mechanically ventilated with adjustments in minute volume to maintain normocapnia and normoxemia. Cardiorespiratory variables were recorded. A numeric comfort score was assigned hourly to assess efficacy. Mouth care, position change, and physiotherapy were performed every 6 hours. Urine output was measured every 4 hours.

Results—Use of both protocols maintained dogs within optimal comfort ranges > 85% of the time. The first dog in each group was excluded from the study. Significant decreases in heart rate, oxygen consumption, and oxygen extraction ratio were evident for protocol 1. Cardiac index values in ventilated dogs were lower than values reported for healthy unsedated dogs. Oxygen delivery, lactate concentration, and arterial base excess remained within reference ranges for both protocols.

Conclusions and Clinical Relevance—Use of both protocols was effective for facilitating mechanical ventilation. A reduction in cardiac index was detected for both protocols as a result of bradycardia. However, oxygen delivery and global tissue perfusion were not negatively affected.

All Time Past Year Past 30 Days
Abstract Views 59 0 0
Full Text Views 12874 12399 132
PDF Downloads 430 234 12
Advertisement