The proneposition can be used for the planning of adjuvant radio- therapy after conservative breast surgery in order to deliver less irradiation to lung and cardiac tissue. In the present study, we com- pared the results of three-dimensional conformal radiotherapy plan- ning for five patients irradiated in the supine and proneposition. Tumor stage was T1N0M0 in four patients and T1N1M0 in one. All patients had been previously submitted to conservative breast surgery. Breast size was large in three patients and moderate in the other two. Irradiation in the proneposition was performed using an immobiliza- tion foam pad with a hole cut into it to accommodate the breast so that it would hang down away from the chest wall. Dose-volume histo- grams showed that mean irradiation doses reaching the ipsilateral lung were 8.3 ± 3.6 Gy with the patient in the supine position and 1.4 ± 1.0 Gy with the patient in the proneposition (P = 0.043). The values for the contralateral lung were 1.3 ± 0.7 and 0.3 ± 0.1 Gy (P = 0.043) and the values for cardiac tissue were 4.6 ± 1.6 and 3.0 ± 1.7 Gy (P = 0.079), respectively. Thus, the dose-volume histograms demonstrated that lung tissue irradiation was significantly lower with the patient in the proneposition than in the supine position. Large-breasted women appeared to benefit most from irradiation in the proneposition. Proneposition breast irradiation appears to be a simple and effective alterna- tive to the conventional supine position for patients with large breasts, since they are subjected to lower pulmonary doses which may cause less pulmonary side effects in the future.
improvement in the PaO 2 /FiO 2 ratio and in the tidal volume. It is possible that the disappointing results regarding mortality in that study were due to the short time spent in the proneposition. In that paper, there was no information regarding the maximum improvement in the proneposition over the course of time. This means that it is unknown how many patients were still improving their oxygenation at the end of the prone period. In our study, we have shown that, although 65% of the patients did improve within the first 30 minutes in PP, there was a continuous improvement in oxygenation, with the major- ity of the patients achieving the maximum PaO 2 /FiO 2 ratio in the third hour after prone. This means that they were still improving at the end of the three hours, thus suggesting that a longer period of PP would be needed to achieve the maximum response. This was also suggested by a recent study in which 11 patients put in the proneposition for up to 18 hours did show a continuous improvement in oxygenation. 19 Unfortunately, this latter study
Following its previous spread throughout Eastern China, human cases of H7N9 avian flu were reported in Guangdong Province during the winter of 2013. Because of its persistent presence in chickens, H7N9 influenza virus may become a long-term threat to public health . Statis- tics provided by the Guangdong Center for Disease Control and Prevention (CDC) indicated that from January, 2014 to mid-April, 2014, there were 103 confirmed cases and 33 fatal cases of H7N9 avian flu. Among the 103 confirmed cases, ~ 70% of the patients became critically ill. In addition to fever and cough, avian flu can manifest with rapidly progressive severe pneumo- nia and severe acute respiratory distress syndrome (ARDS). In 2014, the Chinese Ministry of Health (MOH) developed policies and procedures designed to protect against H7N9 virus infection (2014 Guidelines for Prevention and Control of Human H7N9 Avian Flu) that rec- ommended the use of both protective proneposition ventilation (PPV) and supine position ventilation (SPV) when treating H7N9 infected patients with respiratory dysfunction. Hence, a protective PPV strategy has been utilized with some patients receiving antiviral therapy, and who exhibited refractory hypoxemia and persistent pulmonary exudation. However, very few studies have evaluated the effect of PPV on the outcome of patients with severe ARDS accom- panied by an avian flu infection. Our current multicenter retrospective study was conducted to examine the efficacy achieved when using PPV in a small population of H7N9 avian flu patients in Guangdong Province, China.
Regarding the motor patterns, the following was observed: a) the UL remained under the body when transferring from supine to prone positions; b) there was lack of support from the UL in the proneposition, with incomplete cervical exten- sion, poor range to grab objects, and lower limb extensor pattern; c) the patient was not able to transfer from the supine to the sitting position; d) the patient did not remain seated with trunk control and hands free for long or at backward movements; e) the patient did not perform trans- fers from the sitting position; f) the patient demonstrated weight-bearing in the standing position, and simulated steps with support from the pelvic girdle; g) the patient showed self-locomotion for short distances using the rolling move- ment, and, when prone, tried to crawl without alternating movement of the lower limbs; and h) absence of bimanual
as possible. The measured variable was the Manual Reaction Time (MRT), i.e., the latency between the appearance of the picture and the execution of the answer. Each participant was tested in two sessions, carried out on consecutive days: one session with the hand in the proneposition and the other in the supine position. For the proneposition, the subjects kept the palm of their hands facing downwards and flexed their forefinger to push the answer button. For the supine position, the participants kept the palm of their hands facing upwards and flexed their forefingers to push the button, which had been turned 180 o .
Thus, we postulate that the proneposition alone would not be capable of improving oxygenation without PEEP in ARDS, in which we know there is a lower quantity of potentially recruitable pulmonary tissue due to the greater numbers of alveoli filled with liquid, which need greater pressure for alveoli to open. Nevertheless, some authors have demonstrated improved oxygenation when patients are placed in the proneposition even on ZEEP, such as Vieillard-Baron et al., 29 who compared ZEEP and PEEP = 6
The association of recruitment maneuvers with prone positioning was crucial to the management of the hypox- emia, serving as a bridge to the recovery of the lungs. Alveolar damage associated with necrotizing bronchiolitis with extensive hemorrhage has been described as the major histological pattern for patients with H1N1 pneumonia and respiratory failure, 8 and we believe that this type of injury can be limited by alveolar recruitment interventions such as RM, prone positioning, and corticosteroid use. Recruitment maneuvers in ARDS, through the application of high inspiratory pressures for short periods of time 1 , can be used to open collapsed alveoli and allow a more homo- geneous distribution of the ventilation, potentially reducing the lung injury induced by mechanical ventilation. Mechanical ventilation in the proneposition can be used as a rescue therapy for patients with refractory hypoxemia. 7
The majority of patients were positioned in proneposition (63%) for PCNL and had a single puncture performed (78%). Stone-free rate after auxiliary procedures was 67%. Mean drop in the hematocrit level was 8.1% and it was used to es- timate the intra-operative bleeding. Blood trans- fusion was required in five (18.5%) cases. Mean operative time was 138.3±36.7 minutes and mean length of hospital stay was 5.6±3.9 (range 2 to 16)
Regarding training and patient decubitus, 81% of performers were trained to obtain renal access in proneposition and 64% in supine. Al- though prone has been the preferred position for PCNL for decades, the supine decubitus po- sition (15, 16) is becoming more popular among responders of our survey which contrasts with CROES data, that shows it is currently used in only 20% of centers worldwide and its practice is almost null in North America and Australia (11, 16). The proneposition was preferred for both usual (61.3%) and complex cases (60%).
Recently, there have been many reports about PCNL in the supine position (9-11). The po- tential advantages of supine position in PCNL are as follows. Firstly, the surgeon can work while sit- ting on chairs during the whole procedures which is more comfortable. Secondly, the supine position has important anesthesiological advantages, such as a low incidence of cardiovascular and respira- tory problems. Some authors believe that the in- cidence of colonic injuries is lower in supine po- sition than that in proneposition (11,12). What’s more, the supine position allows a simultaneous retrograde approach to the ureter and renal pelvis, with both rigid and fl exible scopes, for contem- poraneous treatment of ureteral or complex renal stones. However, every coin has its two sides, so does the supine position. The obviously antero-
To the best of our knowledge, this study is the most com- prehensive study till date investigating IOP changes in the proneposition. IOP was measured in the proneposition at the 10th, 60th and 120th minutes of operation. We found that IOP was highest at the 60th minute, and it reduced slightly at the 120th minute, which was still significantly higher than baseline values. While our study on IOP changes during the operation has a variation curve similar to other studies, any differences may be linked to erroneous high measurements due to excessive eyelid opening or pressure on the globe.
The article entitled ‘‘Effect of head rotation on intraocu- lar pressure in proneposition: randomized study’’ recently published in the Brazilian Journal of Anesthesiology calls the reader’s attention to the importance of the good practice of anesthesia in order to prevent serious complication to patients undergoing surgery in proneposition, which is the loss of vision. 1
Preterm newborns have some peculiarities that lead to greater rib cage instability. Proper body positioning can reduce that disadvantage, facilitating respiratory work. The scientific literature indicates the proneposition as advantageous for thoracoabdominal biomechanics because it increases the diaphragm’s zone of apposition, stabilizes the rib cage, and reduces energy expenditure. However, the literature does not describe the response of cardiorespiratory indicators to supine posture with a resource that promotes rib cage stabilization.
newborn infants admitted to a neonatal intensive care unit who are not stratiied according to gestational or postnatal age. hese indings suggest a possible correlation between the proneposition and a reduction of stress in premature newborn infants. Although the measurements of temperature, heart rate, and peripheral oxygen saturation did not seem to be inluenced by body position, future studies with improved methodology and larger samples may be able to detect a correlation between these variables and a population more sensitive to postural intervention.
The MPP could be placed upon a normal mattress and hence would be compatible with the existing bed at home. The main purpose of the MPP was to provide a comfortable prone sleep position. After lying on the MPP, the temperature-sensitive visco- elastic material moulded to the body shape, which helped the subject maintain the proneposition during the night. Although lateral positioning would be pos- sible, supine positioning was dif ﬁcult (Figure 2).
16. Albert RK, Hubmayr RD. The proneposition eliminates compression of the lungs by the heart. Am J Respir Crit Care Med. 2000;161:1660–5. 17. Trezena AG, Silva ZL, Oliveira-Filho RM, Damazo AS, Straus AH, Takahashi HK, Oliani SM, Tavares de Lima W. Differential regulation of the release of tumor necrosis factor- α and of eicosanoids by mast cells in rat airways after antigen challenge. Mediat. Inflam. 2003;12:237–46.
Despite advances in the understanding of ARDS pathogenesis, it still results in signiicant mortality. he alveolar recruitment maneuver and proneposition seem signiicantly contributive for ARDS patients’ treat- ment, aiming oxygenation improvement and refrac- tory hypoxemia complications minimization, and lung complacency reduction. However there are few papers in the literature evaluating these maneuvers in acute respiratory distress syndrome treatment. As those are mostly experimental, more investigation on this subject is granted, and evidences of its clinical usefulness.