Maternal and fetal arterial blood gas data in normotensive, singleton, isoflurane anesthetized sheep at 124-126 days of gestation.

The aim of this case series was to describe the differences between maternal and fetal blood-gas results during anesthesia. Sixteen singleton adult merino ewes weighing 60.1 ± 5.1 kg at 125.7 d (124 to 126 d) gestation were anesthetized. Maternal (radial) and fetal (umbilical) arterial blood gas samples were collected 79 ± 6 min after the start of anesthesia if maternal mean arterial pressure (MAP) was stable and > 65 mmHg. Fetal pH, partial arterial pressure of oxygen (PaO2), glucose, arterial hemoglobin oxygen saturation (SaO2), sodium, and chloride were significantly lower and fetal partial arterial pressure of carbon dioxide (PaCO2), lactate, hematocrit, total hemoglobin, potassium, and calcium were significantly higher than maternal blood-gas values. Fetal pH, PaO2, and BE were lower and fetal lactate was higher than fetal umbilical arterial samples previously reported, which may indicate a non-reassuring fetal status. Further refinement of the ovine experimental model is warranted with fetal monitoring during maternal anesthesia.

L'objectif de l'étude était de décrire les différences dans les résultats d'analyse des gaz sanguins maternel et foetal durant l'anesthésie. Seize brebis mérinos primipares pesant 60,1 ± 5,1 kg à 125,7 j (124 à 126 j) de gestation ont été anesthésiées. Des échantillons de sang artériel maternel (radiale) et foetal (ombilicale) ont été prélevés 79 ± 6 min après le début de l'anesthésie si la pression artérielle moyenne (PAM) maternelle était stable et > 65 mmHg. Pour le sang foetal, les valeurs de pH, de la pression artérielle partielle en oxygène (PaO2), du glucose, de la saturation en oxygène de l'hémoglobine artérielle (SaO2), du sodium, et du chlorure étaient significativement inférieures, et les valeurs de la pression artérielle partielle en dioxyde de carbone (PaCO2), du lactate, de l'hématocrite, de l'hémoglobine totale, du potassium, et du calcium étaient significativement supérieures que celles du sang maternel. Les valeurs foetales du pH, de la PaO2, et de BE étaient plus basses et le lactate foetal étaient plus élevées que les valeurs d'échantillons provenant du sang artériel ombilical foetal rapportées précédemment, ce qui pourrait indiquer un statut foetal non-rassurant. Des améliorations de ce modèle expérimental ovin sont souhaitées avec un suivi foetal durant une anesthésie maternelle.(Traduit par Docteur Serge Messier).

Unilateral retrobulbar hematoma following maxillary nerve block in a dog.

OBJECTIVE: To describe the clinical findings and management of a case of retrobulbar hematoma formation secondary to performance of a maxillary nerve block in a dog. CASE SUMMARY: An 11-year-old dog was presented for a routine dental procedure including dental extraction to be performed under general anesthesia. After premedication with intramuscular methadone, anesthesia was induced with intravenous alfaxalone until depth of anesthesia was sufficient to allow orotracheal intubation. Anesthesia was maintained with isoflurane delivered in 100% oxygen. A bilateral maxillary nerve block was performed. During administration of the left nerve block, blood was aspirated. Twenty minutes after placement of the left maxillary nerve block, exophthalmos, periorbital swelling, extensive scleral hemorrhage, and ecchymosis with a 2 × 2 cm region of moderate swelling on the palatal mucosa around the injection site were noted. These lesions were the result of retrobulbar hematoma formation following vessel puncture. Treatment included immediate creation of a drainage tract and administration of anti-inflammatories (carprofen 2 mg/kg PO q 12 h for 7 days), broad spectrum antimicrobial therapy (cefovicin 8 mg/kg SC once), and eye drops (viscotears, 2 drops OS q 12 h for 7 days). The periorbital swelling was significantly reduced within 1 hour of drainage and had almost completely resolved 1 week later. NEW OR UNIQUE INFORMATION PROVIDED: This clinical report details the development and successful management of a unilateral retrobulbar hemorrhage following maxillary nerve block. Management of this condition requires prompt recognition and treatment to prevent permanent damage to the eye. The cornerstone of treatment is drainage, which rapidly decreases the increased intraorbital and intraocular pressure. To our knowledge, this is the first documentation of this complication in the English language literature.