GASTROINTESTINAL TUBE INSERTION TECHNIQUES IN CRITICAL PATIENTS: SCOPING REVIEW

ABSTRACT Objective to map the production of knowledge about the different techniques of gastrointestinal tube insertion in critically ill and/or coma patients. Method scope review carried out in December 2020 in ten data sources, following the assumptions established by the Joanna Briggs Institute (2020) and the PRISMA-ScR protocol. Results 25 studies were selected and analyzed, identifying as the main techniques for insertion of gastrointestinal tube in critically ill and/or coma patients: techniques without the aid of instrumentals, such as head flexion, lateral neck pressure, tube freezing, measurement with corrected formula of the tip of the ear-lobe tip-xiphoid process, Sellick´s maneuver, cricoid cartilage compression, SORT maneuver and gastric insufflation. In addition to techniques with the aid of instruments, such as the use of laryngoscopes and video laryngoscopes. It is noteworthy that, in order to facilitate insertion, the use of ultrasound examination, radiological, endoscopic and fluoroscopy were also identified. Conclusions the evidence analyzed reveals that there is no specific gastrointestinal tube insertion technique for universally accepted critically ill patients.

Comparison of GlideScope™ visualization and neck flexion with lateral neck pressure nasogastric tube insertion techniques in anesthetized patients: a randomized clinical study

Objective Nasogastric tube (NGT) insertion in anesthetized and intubated patients can be challenging, even for experienced anesthesiologists. Various techniques have been proposed to facilitate NGT insertion in these patients. This study aimed to compare the success rate and time required for NGT insertion between GlideScope™ visualization and neck flexion, with lateral neck pressure techniques. Material and methods This randomized clinical trial was performed at a teaching hospital on 86 adult patients undergoing abdominal surgery, under relaxant general anesthesia, who required intraoperative NGT insertion. The patients were randomized into two groups, the GlideScope™ group (group G) and the neck flexion with lateral neck pressure group (group F). The success rate of the first and second attempts, duration of insertion, and complications were recorded. Results The total success rate was 79.1% in group G, compared with 76.7% in group F (P = 1). The median time required for NGT insertion was significantly longer in group G, for both first and second attempts (97 vs 42 s P < 0.001) and (70 vs 48.5 s P = 0.015), respectively. Complications were reported in 23 patients (53.5%) in group G and 13 patients (30.2%) in group F. Bleeding and kinking were the most common complications for both techniques. Conclusion Using GlideScope™ visualization to facilitate NGT insertion was comparable to neck flexion with lateral neck pressure technique, in the degree of success rates of insertion. Although complications were not statistically significant between groups, neck flexion with lateral neck pressure technique was significantly less time-consuming for both first and second attempts. Trial registration Retrospectively registered: Thai Clinical Trial Registry (TCTR)20171229003. Registered on 19 December 2017

MON-458 Elevated Thyroglobulin Level in Benign Thyroid Nodule

Background: Elevated thyroglobulin levels are most commonly associated with differentiated thyroid carcinoma and these levels are often used to monitor for disease recurrence. Thyroglobulin antibody levels can be elevated in both Hashimoto’s Thyroiditis and Graves’ Disease and these antibodies can interfere with thyroglobulin levels as detailed by Spencer, Wang (1). With benign thyroid nodules, there is limited research regarding thyroglobulin levels as studied in Chinnappa, et al (2). Clinical Case: A 31-year woman presented with a palpable thyroid nodule and dysphagia. Her primary care physician ordered thyroid labs including normal TSH (1.3 mIU/L, n0.4-4 mIU/L), normal thyroid peroxidase antibody (56 units, n&lt;250units), normal thyroglobulin antibody level (&lt;1 IU/mL, n&lt;1 IU/mL), and elevated thyroglobulin level (469.1 ng/mL, n2.8-40.9 ng/mL). Her thyroglobulin levels remained elevated on repeat testing (224.4 ng/mL, n2.8-40.9) one month later. In addition, her thyroglobulin lab studies were repeated with HAMA treatment and remained elevated (277.7 ng/mL, n2.8-40.9). Office ultrasound showed longest dimension of nodule to be 5 cm and patient received FNA biopsy. Biopsy results were reported as a benign nodule and it was recommended to follow-up in 12 months. Six months later the patient reported having increasing dysphagia. She underwent Barium swallow which showed no abnormalities. She had a growth increase of 35% on repeat imaging along with increasing neck pressure and discomfort and was referred to an ENT for surgery. Final pathology after left thyroid and isthmus thyroidectomy was reported as “Multinodular hyperplasia with background thyroid parenchyma histologically unremarkable. Negative for malignancy.” Thyroglobulin levels subsequently returned to within the normal range and the patient’s dysphagia resolved. Conclusion: Thyroglobulin levels can be markedly elevated with benign thyroid nodules, which can mislead physicians and increase concern for thyroid cancer. References: (1) Spencer, CA, Wang, CC. Thyroglobulin measurement. Techniques, clinical benefits, and pitfalls. Endocrinol Metab Clin North Am. 1995 Dec; 24(4): 841-63. (2) Chinnappa, P, Taguba, L, Arciaga, R, Faiman, C, Siperstein, A, Mehta, AE, Reddy SK, Nasr, C, Gupta MK. Detection of thyrotropin-receptor messenger ribonucleic acid (mRNA) and thyroglobulin mRNA transcripts in peripheral blood of patients with thyroid disease: sensitive and specific markers for thyroid cancer. J Clin Endocrinol Metab. 2004 Aug;89(8):3705-9.

SAT-195 The Diagnosis and Management of a Functional Paravertebral Paraganglioma

A 32-year-old male presented with a 4-year history of palpitations, diaphoresis, and orthostatic hypotension. One year prior to presentation, he began experiencing severe, episodic headaches and neck pressure. Neurological work-up included an MRI head, neck, and spine, identifying a left posterior mediastinal lesion adjacent to the T5 vertebral body, approximately 2.4 x 2.0 cm. A community surgical center attempted mass resection via Video -assisted (VATS) approach. Resection was aborted intraoperatively due to a hypertensive crisis following lesion manipulation, with his systolic blood pressure increasing above 325 mmHg. Subsequent evaluation revealed a 24-hour urine norepinephrine of 6117 nmol/d (normal &lt;575) and normetanephrines of 16.6 umol/d (normal &lt;3.4). An MIBG study showed intense tracer avidity in the left paraspinal lesion and minimal uptake in the adrenal glands. A functional paravertebral paraganglioma was diagnosed and the patient was initiated on alpha and beta-blockade in preparation for staged combined treatment. Spinal angiography was performed to define the arterial supply of spinal cord and tumor, which confirmed a hypervascular left thoracic paraspinal tumor. Arterial supply emanated from the left T4 intercostal and left supreme intercostal arteries and a prominent draining vein was present. Trans-arterial particle embolization was performed via both arteries with minimal residual tumor blush present post procedure. Successful VATS excision of the tumor was completed one week after arterial embolization with minimal blood loss. Pathology of the resected tumor revealed an overall intact tumor that stained diffusely positive with synaptophysin and sustentacular cells highlighted by S100 protein with a few foci of coagulative necrosis. Episodes of hypertension (maximum BP 210/80) occurred during embolization and surgical resection with vascular manipulation. These were managed with intraoperative nitroprusside and phentolamine. Peri-procedural plasma metanephrine and cathecholamine levels were collected. Normetanephrine levels (normal &lt;=0.89 nmol/L) were 4.66 before embolization, &gt;6.25 after embolization, 3.70 the day after embolization, 4.10 before VATS, and 0.69 after VATS. Norepinephrine levels (normal 0.8–3.4 nmol/L) were 24.3, 111.7, 61.1, 19.6, and 4 respectively. Genetic testing showed no hereditary predisposition. Discussion: Functional neuroendocrine tumours may be difficult to diagnose due to the wide variety of clinical presentations and must be considered when investigating a vascular mediastinal tumor. In our case, pre-operative embolization did not normalise plasma catecholamine levels, likely from incomplete arterial embolization, but helped reduce intra-operative surgical bleeding risk. Alpha- and beta-blockade should be continued until surgical resection, with dose adjustment as required.

Comparison of the GlideScopeTM Visualization and Neck Flexion with Lateral Neck Pressure Nasogastric Tube Insertion techniques in Anaesthetized Patients: A Prospective Randomized Clinical Study

Background Nasogastric tube (NGT) insertion in anaesthetized and intubated patients can be challenging even for experienced anesthesiologists. Various techniques have been proposed to facilitate NGT insertion in these patients. This study aimed to compare the success rate and time required for NGT insertion between the GlideScope TM visualization and neck flexion with lateral neck pressure techniques. Methods This randomized clinical trial was performed at a teaching hospital on 86 adult patients undergoing abdominal surgery under relaxant general anaesthesia who required intraoperative NGT insertion. The patients were randomized into two groups, the GlideScope TM group (group G) and the neck flexion with lateral neck pressure group (group F). The success rate of first and second attempts, duration of insertion, and complications were recorded. Results The total success rate was 79.1% in Group G compared with 76.7% in Group F (P=1) The median time required for NGT insertion was significantly longer in Group G, for both first and second attempts (97 vs 42 seconds P<0.001) and (70 vs 48.5 seconds P=0.015), respectively. Complications were reported in 23 patients (53.5%) in group G and 13 patients (30.2%) in group F. Bleeding and kinking were the most common complications in both techniques. Conclusions Using GlideScope TM visualization to facilitate NGT insertion was comparable to neck flexion with lateral neck pressure technique in degree of success rate of insertion and complications were not statistically significant between groups, while neck flexion with lateral neck pressure technique was less time-consuming significantly both first and second attempts.

The carotid baroreflex modifies the pressor threshold of the muscle metaboreflex in humans

The purpose of the present study was to test our hypothesis that unloading the carotid baroreceptors alters the threshold and gain of the muscle metaboreflex in humans. Ten healthy subjects performed a static handgrip exercise at 50% of maximum voluntary contraction. Contraction was sustained for 15, 30, 45, and 60 s and was followed by 3 min of forearm circulatory arrest, during which forearm muscular pH is known to decrease linearly with increasing contraction time. The carotid baroreceptors were unloaded by applying 0.1-Hz sinusoidal neck pressure (oscillating from +15 to +50 mmHg) during ischemia. We estimated the threshold and gain of the muscle metaboreflex by analyzing the relationship between the cardiovascular responses during ischemia and the amount of work done during the exercise. In the condition with unloading of the carotid baroreceptors, the muscle metaboreflex thresholds for mean arterial blood pressure (MAP) and total vascular resistance (TVR) corresponded to significantly lower work levels than the control condition (threshold for MAP: 795 ± 102 vs. 662 ± 208 mmHg and threshold for TVR: 818 ± 213 vs. 572 ± 292 kg·s, P < 0.05), but the gains did not differ between the two conditions (gain for MAP: 4.9 ± 1.7 vs. 4.4 ± 1.6 mmHg·kg·s−1·100 and gain for TVR: 1.3 ± 0.8 vs. 1.3 ± 0.7 mmHg·l−1·min−1·kg·s−1·100). We conclude that the carotid baroreflex modifies the muscle metaboreflex threshold in humans. Our results suggest the carotid baroreflex brakes the muscle metaboreflex, thereby inhibiting muscle metaboreflex-mediated pressor and vasoconstriction responses. NEW & NOTEWORTHY We found that unloading the carotid baroreceptors shifts the pressor threshold of the muscle metaboreflex toward lower metabolic stimulation levels in humans. This finding indicates that, in the normal loading state, the carotid baroreflex inhibits the muscle metaboreflex pressor response by shifting the reflex threshold to higher metabolic stimulation levels.

Carotid baroreflex control of heart rate is enhanced, while control of mean arterial pressure is preserved during whole body heat stress in young healthy men

Whole body heat stress (WBH) results in numerous cardiovascular alterations that ultimately reduce orthostatic tolerance. While impaired carotid baroreflex (CBR) function during WBH has been reported as a potential reason for this decrement, study design considerations may limit interpretation of previous findings. We sought to test the hypothesis that CBR function is unaltered during WBH. CBR function was assessed in 10 healthy male subjects (age: 26 ± 3; height: 185 ± 7 cm; weight: 82 ± 10 kg; BMI: 24 ± 3 kg/m2; means ± SD) using 5-s trials of neck pressure (+45, +30, and +15 Torr) and neck suction (−20, −40, −60, and −80 Torr) during normothermia (NT) and passive WBH (Δ core temp ∼1°C). Analyses of stimulus response curves (four-parameter logistic model) for CBR control of heart rate (CBR-HR) and mean arterial pressure (CBR-MAP), as well as separate two-way ANOVA of the hypotensive and hypertensive stimuli (factor 1: thermal condition, factor 2: chamber pressure), were performed. For CBR-HR, maximal gain was increased during WBH (−0.73 ± 0.11) compared with NT (−0.39 ± 0.04, mean ± SE, P = 0.03). In addition, the CBR-HR responding range was increased during WBH (33 ± 5) compared with NT (19 ± 2 bpm, P = 0.03). Separate analysis of hypertensive stimulation revealed enhanced HR responses during WBH at −40, −60, and −80 Torr (condition × chamber pressure interaction, P = 0.049) compared with NT. For CBR-MAP, both logistic analysis and separate two-way ANOVA revealed no differences during WBH. Therefore, in response to passive WBH, CBR control of heart rate (enhanced) and arterial pressure (no change) is well preserved.