Effect of Analgesic Low-Dose Ketamine Infusions on the Cardiovascular Response: A Retrospective Analysis.

BACKGROUND: Low-dose ketamine infusion (LDKI) has shown effectiveness for treating acute pain associated with surgical and nonsurgical (traumatic, neuropathic, and acute cancer-related) origin as an adjuvant to opioids. The increasing use of LDKI as an opioid-sparing agent in multimodal analgesia requires a better understanding of its effects on the cardiovascular response, a known dose-dependent side effect of ketamine administration. We investigated the cardiovascular response of acute pain patients treated with LDKI. OBJECTIVES: The aim of the present study was to evaluate the effect of LDKI in hemodynamic variables (blood pressure [BP] and heart rate [HR]) during LDKI analgesia for up to 48 hours of treatment in an acute pain setting. Secondary objectives were to evaluate psychomimetic effects. STUDY DESIGN: Retrospective unicentric cohort design. SETTING: The study was conducted at an academic university hospital. METHODS: We conducted a single-center retrospective cohort analysis of adult patients who underwent LDKI to treat surgical and nonsurgical acute pain. We obtained data from the Hospital San Vicente Fundación Health Documentation System database and evaluated the medical records of 318 patients with surgical and nonsurgical pain. Patients received a 0.1 mg/kg/h ketamine infusion as part of a multimodal analgesic plan. Baseline systolic BP (SBP), diastolic BP (DBP), mean arterial pressure (MAP), and HR values were compared with those measured after 24 and 48 hours of treatment. Pain level and psychomimetic effects were measured at 24 and 48 hours. Cardiovascular complications and treatment duration were also recorded. Patients with a history of psychiatric, cardiovascular, or cognitive disease were excluded from the study. This study was registered in the clinicaltrials.gov database (identifier: NCT03979105). RESULTS: No statistical differences in SBP, DBP, MAP, or HR were observed when baseline and post-LDKI treatment values were compared (P < 0.05). When comparing hemodynamic variables after exposure to LDKI in patients with and without hypertension, we did not observe statistically significant differences in mean HR, systolic arterial pressure, diastolic arterial pressure, or MAP values at 24 and 48 hours. The frequency of severe pain was reduced from 72% on day 0 to 4.4% on day 1 and 6.2% on day 2 post-LDKI. Observed psychomimetic effects were confusion 4.39%, hallucinations 2.51%, and nightmares 1.25%. No major cardiovascular events were observed. LIMITATIONS: This study was limited by its retrospective design, the lack of a comparative matching cohort, and the good general condition of the majority of patients included in the study. CONCLUSIONS: LDKI (0.1 mg/kg/h) was not associated with significant changes in baseline BP or HR. Our results suggest that as an adjuvant in multimodal analgesia for surgical and nonsurgical acute pain, LDKI has a low impact on the cardiovascular response. KEY WORDS: Ketamine, adverse effects, tachycardia, hypertension, postoperative pain, chronic postsurgical pain.

Evaluation of Sensory Mapping of Erector Spinae Plane Block.

BACKGROUND: Erector spinae plane (ESP) block is an effective regional analgesic technique for thoracic and abdominal pain. The volume of local anesthetic (LA) needed to produce sensory block in the spinal segment is unknown. OBJECTIVES: The aim of the present study was to examine the extent of dermatomal spread following ultrasound-guided administration of ESP block, with a fixed-volume dose of a LA at the midthoracic area for analgesia in acute thoracic pain patients. Secondary objectives were postprocedure analgesia and patient satisfaction. STUDY DESIGN: This research used a prospective unicentric exploratory cohort design. SETTING: The study was conducted at an academic university hospital. METHODS: A total of 18 patients with acute severe chest pain including rib fractures, thoracic postoperative rescue analgesia, zoster herpetic neuritis, and myofascial pain syndrome received ESP block under ultrasound guidance at the T5-T7 levels. Twenty mL of 0.5% plain bupivacaine was injected. Evaluation of the sensory block was carried out 60 minutes following the completion of the ESP block via a change in sensation to pinprick and cold methods. The Visual Analog Scale (VAS) for pain was recorded one hour after the procedure. Patient satisfaction was reported using a 4-point Likert scale. This study was registered with the clinicaltrials.gov database (identifier: NCT03831581). RESULTS: Sixteen patients had a successful ESP block; 2 patients were excluded for a failed block. The mean dermatomal spread was 9 (range, 8-11). VAS scores improved by at least 50% from baseline (P < .05), one hour after the ESP block. The degree of satisfaction reported by all patients on the Likert scale was 4 points. No major complications were observed. LIMITATIONS: This study was limited by its sample size. CONCLUSIONS: An ultrasound-guided ESP block with a single injection at the midthoracic level with 20 mL of 0.5% plain bupivacaine provides a mean dermatomal spread of 9 dermatomes (range, 8-11) with a high rate of analgesic efficacy and low incidence of adverse effects. KEY WORDS: Acute pain, dermatomal spread, erector spine plane nerve block, thoracic pain, thoracic postoperative analgesia.

A importância da investigação de variações anatômicas das células etmoidais através da tomografia computadorizada no planejamentoda cirurgia endoscópica nasal: [revisão] / The importance of investigation of anatomic variations in the ethmoid cells by computerized tomography in the planning of endoscopic nasal surgery: [review]

As células etmoidais compreendem diversas cavidades que podem apresentar variações anatômicasnos indivíduos. Algumas variações merecem atenção quando associadas a sinusopatias e à necessidade de intervenção cirúrgica. A tomografia computadorizada, considerada padrão-ouro na investigação de doenças da cavidade nasal e no mapeamento anatômico dos seios paranasais, oferece informações acerca da anatomia das células etmoidais, essenciais para a minimização dos riscos cirúrgicos. O presente trabalho tem o objetivo de, mediante revisão bibliográfica, avaliar aimportância da tomografia computadorizada na investigação de variações anatômicas das célulasetmoidais para o planejamento pré-cirúrgico. Células não recorrentes, como as células de Haller, célula de Onodi e a aeração do agger nasi, permitem que a abordagem endoscópica seja planejada com cautela. A avaliação do teto etmoidal resulta em maior segurança quanto aos limites superiores da fossa nasal. O tamanho e o nível de pneumatização da bolha etmoidal, da crista etmoidal e da concha nasal média são importantes ao se avaliar os acessos endoscópicos, a gravidade dadoença, e até mesmo sua origem.

The ethmoidal cells comprise many cavities that show many anatomicalvariations. Some of these variations deserve special attention when associated with sinusitis and the need of surgery. Computed tomography, considered a gold standard on the pathological investigation of the nasal cavity and the anatomic descriptionof paranasal sinus, offers informations about these cells, essential to minimize the surgical risks. The authors present a bibliographic revision of the importance of computed tomography on the investigation of anatomic variations of ethmoid cells. Not recurrent cells in all individuals, like Haller's cells, Onodi's cells and pneumatization of agger nasi, will do the endoscopic approach withprecaution. The ethmoidal roof evaluation will result in more safetyon the upper limits of the nasal cavity. The size and pneumatization level of ethmoidal bulla, ethmoidal crest, and middle nasal concha are important on the evaluation of the endoscopic accesses and the gravity of the striked pathology and even diagnose your origin.