Predictors of difficult videolaryngoscopy with GlideScope® or C-MAC® with D-blade: secondary analysis from a large comparative videolaryngoscopy trial.

BACKGROUND: Tracheal intubation using acute-angle videolaryngoscopy achieves high success rates, but is not without difficulty. We aimed to determine predictors of 'difficult videolaryngoscopy'. METHODS: We performed a secondary analysis of a data set (n=1100) gathered from a multicentre prospective randomized controlled trial of patients for whom difficult direct laryngoscopy was anticipated and who were intubated with one of two videolaryngoscopy devices (GlideScope(®) or C-MAC(®) with D-blade). 'Difficult videolaryngoscopy' was defined as 'first intubation time >60 s' or 'first attempt intubation failure'. A multivariate logistic regression model along with stepwise model selection techniques was performed to determine independent predictors of difficult videolaryngoscopy. RESULTS: Of 1100 patients, 301 were identified as difficult videolaryngoscopies. By univariate analysis, head and neck position, provider, type of surgery, and mouth opening were associated with difficult videolaryngoscopy (P<0.05). According to the multivariate logistic regression model, characteristics associated with greater risk for difficult videolaryngoscopy were as follows: (i) head and neck position of 'supine sniffing' vs 'supine neutral' {odds ratio (OR) 1.63, 95% confidence interval (CI) [1.14, 2.31]}; (ii) undergoing otolaryngologic or cardiac surgery vs general surgery (OR 1.89, 95% CI [1.19, 3.01] and OR 6.13, 95% CI [1.85, 20.37], respectively); (iii) intubation performed by an attending anaesthestist vs a supervised resident (OR 1.83, 95% CI [1.14, 2.92]); and (iv) small mouth opening (OR 1.18, 95% CI [1.02, 1.36]). CONCLUSION: This secondary analysis of an existing data set indicates four covariates associated with difficult acute-angle videolaryngoscopy, of which patient position and provider level are modifiable.

A randomised controlled trial of radial artery cannulation guided by Doppler vs. palpation vs. ultrasound.

We randomly allocated 749 participants to radial artery cannulation by anaesthetic trainees, guided by Doppler (244), palpation (256) or ultrasound (249). Ultrasound increased the rate of cannulation at the first attempt by 14% (95% CI 5-22%), from 39% with Doppler or palpation, p = 0.002 for both. There were no differences in the rates of cannulation 5 min after the procedure started: 147/244 (60%) with Doppler; 160/256 (63%) with palpation; and 171/249 (69%) with ultrasound, p = 0.13.

Involved Node, Site, Field and Residual Volume Radiotherapy for Lymphoma: A Comparison of Organ at Risk Dosimetry and Second Malignancy Risks.

AIMS: Recent radiotherapy guidelines for lymphoma have included involved site radiotherapy (ISRT), involved node radiotherapy (INRT) and irradiation of residual volume after full-course chemotherapy. In the absence of late toxicity data, we aim to compare organ at risk (OAR) dose-metrics and calculated second malignancy risks. MATERIALS AND METHODS: Fifteen consecutive patients who had received mediastinal radiotherapy were included. Four radiotherapy plans were generated for each patient using a parallel pair photon technique: (i) involved field radiotherapy (IFRT), (ii) ISRT, (iii) INRT, (iv) residual post-chemotherapy volume. The radiotherapy dose was 30 Gy in 15 fractions. The OARs evaluated were: breasts, lungs, thyroid, heart, oesophagus. Relative and absolute second malignancy rates were estimated using the concept of organ equivalent dose. Significance was defined as P < 0.005. RESULTS: Compared with ISRT, IFRT significantly increased doses to lung, thyroid, heart and oesophagus, whereas INRT and residual volume techniques significantly reduced doses to all OARs. The relative risks of second cancers were significantly higher with IFRT compared with ISRT for lung, breast and thyroid; INRT and residual volume resulted in significantly lower relative risks compared with ISRT for lung, breast and thyroid. The median excess absolute risks of second cancers were consistently lowest for the residual technique and highest for IFRT in terms of thyroid, lung and breast cancers. The risk of oesophageal cancer was similar for all four techniques. Overall, the absolute risk of second cancers was very similar for ISRT and INRT. CONCLUSIONS: Decreasing treatment volumes from IFRT to ISRT, INRT or residual volume reduces radiation exposure to OARs. Second malignancy modelling suggests that this reduction in treatment volumes will lead to a reduction in absolute excess second malignancy. Little difference was observed in second malignancy risks between ISRT and INRT, supporting the use of ISRT in the absence of a pre-chemotherapy positron emission tomography scan in the radiotherapy treatment position.

Patterns of failure after intensity-modulated radiotherapy in head and neck squamous cell carcinoma using compartmental clinical target volume delineation.

AIMS: To determine the pattern of disease recurrence in non-nasopharyngeal head and neck squamous cell carcinoma (HNSCC) patients treated with radical intensity-modulated radiotherapy (IMRT) with or without chemotherapy, and to correlate the sites of locoregional recurrence with radiotherapy target volumes. MATERIALS AND METHODS: In total, 136 patients treated with radical IMRT with or without chemotherapy between 2008 and 2011 for non-nasopharyngeal HNSCC were retrospectively identified. A compartmental approach to clinical target volume (CTV) delineation was routinely utilised during this period and IMRT was delivered using a 5-7 angle step and shoot technique. Locoregional recurrences were reconstructed on the planning computed tomography scan by both deformable image coregistration and by visual assessment, and were analysed in relation to target volumes and dosimetry. RESULTS: The median follow-up was 31 (range 3-53) months. Two year local control, regional control, disease-free survival, distant metastasis-free survival and overall survival were 86, 93, 78, 89 and 79%, respectively. One hundred and twenty of 136 (88%) patients achieved a complete response to treatment and 7/120 (6%) have subsequently had a locoregional recurrence. Analysis of these recurrences revealed five to be infield; one to be marginal to the high-dose CTV; one to be out-of-field. Overall the marginal/out-of-field recurrence rate was 2/136 (1.5%). CONCLUSIONS: IMRT utilising a compartmental approach to CTV delineation was associated with a low rate of marginal/out-of-field recurrence.

Comparison of hematologic toxicity between 3DCRT and IMRT planning in cervical cancer patients after concurrent chemoradiotherapy: a national multi-center study.

PURPOSE: To compare the incidence and severity of acute and chronic hematologic toxicity (HT) in patients treated with three-dimensional conformal radiotherapy (3DCRT) and intensity modulated radiotherapy (IMRT) for curative treatment of cervical cancer and to ascertain the dosimetric parameters of two techniques associated with acute and chronic HT. MATERIALS AND METHODS: A total of 127 patients with cervical cancer receiving concomitant pelvic radiotherapy (RT) and cisplatin were evaluated. Pelvic bone marrow (BM) was contoured for each patient and divided into five sub-regions: lumbosacrum (LS), ilium (IL), lower pelvis (LP), pelvis (P), and whole pelvis (WP). The volume of each BM region receiving 10, 20, 30, and 40 Gy was calculated (V10, -V20, -V30, and -V40). The lowest level of hemoglobin, leukocyte, neutrophil, and platelet counts were obtained during chemoradiotherapy and six months after RT. The nadir values were graded according to Common Terminology Criteria for Adverse Events (version 3.0). RESULTS: Grade 2 or greater acute anemia, leukopenia, neutropenia, thrombocytopenia was observed in 2%, 41.5%, 12% ,and 0% in 3DCRT group and in 27%, 53%, 24.5%, and 4.5% in IMRT group, respectively. Grade 2 or greater chronic anemia, leukopenia, neutropenia, and thrombocytopenia was observed in 11%, 10%, 6%, and 0% in 3DCRT group and in 11%, 9%, 4.5%, and 0% in IMRT group, respectively. LS-V30, 40; IL-V10, 20, 30, 40; LP-V10, 20 ,40; P-V10, 20, 30, 40, and TP-V10, 20, 30, 40 were significantly reduced with IMRT planning compared to 3DCRT planning. Logistic regression analysis of potential predictors showed that none of the dosimetric parameters were significant for predicting acute and chronic HT. CONCLUSION: The present findings showed that IMRT planning reduced irradiated BM volumes compared to 3DCRT planning. However, no difference between the two techniques was observed in terms of acute and chronic HT. Further studies are needed to confirm these results.

Ultrasound visual image-guided vs Doppler auditory-assisted radial artery cannulation in infants and small children by non-expert anaesthesiologists: a randomized prospective study.

BACKGROUND: Cannulation of the radial artery in infants and small children can be challenging, even for the most experienced providers. Utilizing Doppler to aid in radial artery cannulation has been well described. Recent studies have demonstrated the efficacy of ultrasound (US) image-guided vascular access techniques in the paediatric population. The utility of these two techniques, when used by non-expert personnel, has not been studied. METHODS: This is a randomized prospective study to compare the utility of two different radial arterial cannulation techniques in paediatric patients weighing <12 kg: US-guided technique (US group) vs Doppler-assisted technique (Doppler group) when used by trainees with limited experience. The primary objective was to compare the first-attempt success rate between each group. As a secondary objective, success rate within 10 min was compared. RESULTS: The trial was prematurely terminated after 50% of paediatric patients (n=104) were included in the study and 52 of each were randomized to the US or Doppler group. A total of 12 anaesthesia trainees performed radial arterial cannulations. The first-attempt success rate was greater in the US group compared with the Doppler group [17/52 (33%) vs 8/52 (15%), P=0.039, odds ratio (OR): 2.67, confidence interval (CI): 1.03-6.91]. The overall success rate within 10 min was 34/52 (65%) in the US group and 24/52 (46%) in the Doppler group (P=0.048, OR: 2.20, CI: 1.00-4.85). CONCLUSIONS: US-guided radial arterial cannulation in infants and small children provided a greater chance for success at the first attempt compared with the Doppler-assisted technique.

Comparing ultrasound with computerized tomography images to choose electron energy for radiotherapy boost field in breast cancer patients with breast conserving surgery.

PURPOSE: To compare ultrasonographic (US) with computerized tomographic (CT) images in order to choose electron energy for radiotherapy (RT) boost field in patients with breast conserving surgery (BCS). METHODS: Thirty-seven consecutive patients with breast cancer treated by BCS and RT in our department were evaluated. Median age was 49 years (range 32-82). According to the Dokuz Eylul Breast Tumor Group Protocol (DEBTG), in patients with BCS, RT (5000 cGy to the whole breast ± lymphatic area) and boost with electron energy to the primary tumor bed (1000 cGy if surgical margin negative, or 1600 cGy if surgical margin positive was delivered. Before January 2003, the distances between skin-the deepest point of tumor bed (STD), skin-clips (SCD), and skin-fascia (SFD) were measured with US to choose electron energy in boost field. Since then, CT simulation images were used to this purpose. These two imaging systems were compared in this study. Electron energy was selected after measurement of the deepest metallic clips in CT simulation images (90%) or measurement of the STD if no clips were present (10%). RESULTS: Median measurements with US and CT were as follows: STD: US 12 mm (range 4-35), CT 28 mm (range 2-54); SFD: US 25 mm (range 6-57), CT 31 mm (range 2-93); SCD: US 14 mm (range 7-26), CT 29 mm (range 2-68). The median electron energy was 9 MeV é (range 6-12) for US and 12 MeV é (range 6-21) for CT. Concordance in US and CT measurements was 27%. CONCLUSION: This preliminary study reveals that CT-based SCD measurements are deeper than US measurements, and selected electron energy with CT is 3 MeV higher than US. These two factors can affect local control and side effects. We noticed only one local recurrence in 37 patients. We did not evaluate side effects in this study. These could be a subject of a future study.