(Also see Burns, Evaluation and Management and Burns, Thermal). The role of the surgeon within the critical care team is crucial for advice on individual aspects of the patient care such as specific management of the surgical condition, wound care, nutrition and management of anticoagulation in the immediate postoperative period. Patients presenting with severe or critical burns require rapid specific management, in standardized environments, due to the unique pattern of evolution and complications in the face of an excessive systemic response to injury, with severe hypermetabolic and immunoinflammatory Dec 1, 2023 · Severe burns, often defined as those covering more than 20% of total body surface area (TBSA), often create significant alterations in physiology. Jun 17, 2009 · Alcohol-use disorders (AUDs) encompass a spectrum of disorders, including excessive use, abuse, dependence, and addiction. Details of burn classification, burn management in children, treatment of minor burns, and other issues related to burn management are discussed separately. Low V T was used in 74% of patients, median V T size was 7. The majority of the others will be managed by hospitals with Jun 24, 2016 · In a subgroup of hand burns, additional benefits were seen as these patients exhibited earlier time to wound closure and better long-term results. Paediatric Guideline – Burn Dressings; Paediatric Guideline – Fluid Resuscitation; Paediatric Guideline – Infection Management; Paediatric Guideline – Management of Airway Burns and Inhalation Injury Jan 9, 2015 · Although evidence-based strategies to improve outcome are lacking, prognosis of critically ill burn patients has much improved over the last 20 years thanks to refined critical care and surgical techniques . Jan 23, 2023 · Most burns are small and are treated at home or by local providers as outpatients. Randomized clinical trials identifying the best strategies for burn patients are lacking. Focus on the major priorities of any trauma patient. 58 A point prevalence study among ICU patients in France found a prevalence of pressure injuries of 18. key woRdS: Burn patient, Intensive Care Unit, Rehabilitation, Physiotherapy AbbreviAtion List: - Prevention and management of atelectasis . Dec 1, 2023 · Patients with severe burns often receive complex management in intensive care unit (ICU) settings in the acute period after burn. 2 In nonverbal patients (young children and noncommunicative adults), observational scales and physiological indicators, such as heart rate and blood pressure, are used to gauge pain. Keywords burn, ICU, resuscitation, inhalation, sepsis, nutrition Received January 8, 2010, Received Revised February 19, 2010. Dec 16, 2020 · The surgeon on ICU. Br J Anaesth. Patients with burns >20% total body Introduction Burns are common, with the potential for considerable morbidity and mortality. A modified DELPHI study using the RAND/UCLA (University of California, Los Angeles) Appropriateness Method (RAM) systematically analysed the opinions of an expert panel Aug 17, 2018 · The study was designed as an electronic survey addressed to intensive care unit (ICU) physicians. [2] With improvements to burn care, rates of morbidity and mortality following burns have greatly decreased in the last decade. 7%, with newly Jul 1, 2017 · III. Aug 31, 2020 · The critical care in a severely burn-injured patient requires special attention in resuscitation, haemodynamic monitoring, management of complications, organ support and determinants of outcome. 3 Nonetheless, the acute phase of resuscitation still generates significant controversy and is not a standardized process. In fact, the prolonged exposure to painful stimuli, directly related to the burned surface, causes centralization of pain and persistent pain [18,19]. The management areas are: 1. Additionally, it was well tolerated and contributed to stable management with feeding simplicity. Jan 28, 2023 · 1. 20,21 Agitation is associated with an increase in sedation, ICU and ventilator days, ICU-related infections, and ICU-acquired weakness. A retrospective observational study comparing two 12-patient BICU cohorts (2005/06 and 2010/11) was undertaken. This audit aims to define the characteristics of the victims of major burns and factors that increase mortality and outcome of the protocol-based management in a dedicated burns intensive care unit (BICU). - Improvement of pulmonary ventilation. Initial management of a burn is nursing intensive and focuses primarily on stopping the burning process, maintaining homeostasis by keeping the patient warm, and replacing lost fluid and electrolytes. 2016;117(3):284–96. Legrand M, Guttormsen AB, Berger MM. Follow a protocol to ensure consistency in language. Clinicians must be aware of physiologic changes following burn injury and the implicated impacts on management strategy Sep 1, 2016 · The objective of this study was to assess the quality of readily available evidence regarding critical care aspects of the management of patients with severe burn injuries. Nov 1, 2023 · Having a burn dedicated ward but not a burn dedicated ICU at the study facility meant that inter-unit collaboration was essential to deliver optimal burn patient care in ICU, as ICU clinicians were less likely to be experienced and confident in the management and rehabilitation of burn patients, due to the highly specialized nature of burn care Burn ICU Venous Thromboembolism Prophylaxis Original Date: 08/2019 Last Review Date: 06/2022 Purpose: To delineate venous thromboembolism prophylaxis management in the Burn ICU. Jun 9, 2020 · Anaesthetists and critical care physicians involved in emergency care provision must be equipped with the adequate knowledge and skills to accurately assess and manage patients with severe burns. We implemented Pediatric Severe Burn Guidelines, focusing on improving fluid resuscitation accuracy and providing timely nutritional support. Feb 20, 2024 · The initial assessment and management of the patient with moderate and severe thermal burns will be reviewed here. full thickness circumferential burns requiring q1hr neurovascular exams) Jan 26, 2014 · Consensus regarding optimal burns intensive care (BICU) patient management is lacking. Burn dressing changes can produce feelings of anxiety and distress in both patients and their families. Early operative intervention and wound closure, metabolic interventions, early enteral nutrition, and intensive glucose control have led to continued improvements During the first 24–48 hours after a burn occurs, the patient often goes into burn shock and will require a large amount of IV fluid to keep vital signs within normal limits. 18 Similar findings had previously been reported in a retrospective data analysis of 69 hand burns. Jun 1, 2016 · The authors sought to determine the efficacy of gabapentin in acute burn pain management. If able, use pain assessment tools: patient-reported scales, Burn Specific Pain Anxiety Scale (BSPAS), Critical Care Pain Observation Tool (CPOT). resuscitation management in patients with burns: update. Criteria for extubation of burn patients are examined, as is the need for cuffed endotracheal tubes in pediatric burn patients. The burn patient is best cared for in a dedicated burn center where resuscitation and monitoring concentrate on the pathophysiology of burns, inhalation injury, and edema formation. Strategies to avoid over-resuscitation are discussed, including use of colloid, as well as nurse-driven and computer-guided resuscitation protocols. As resuscitative mortality decreases more patients are surviving to experience multisystem organ failure relating to complications of their injuries. Depth . Perform your primary and secondary survey as you normally would with a trauma patient and address the burns later. 58). Aug 8, 2023 · A variety of factors guide the evaluation and management of burns. Oct 7, 2013 · Burn injury is characterised by a hypermetabolic response with physiologic, catabolic and immune effects. Don’t get distracted by the burns. If not contraindicated, patients should be treated with both anticoagulation and compression devices. Burn care has seen renewed interest in colloid resuscitation, a change in transfusion practice and the development of anti-catabolic therapies. Assess circumstances surrounding the injury. 2014;34(5):498-506. This review critically discusses current practices and recently published data regarding the evaluation . Burn injuries can be under-appreciated trauma [], leading to important mortality and morbidity []. May 10, 2024 · The nursing assessment focuses on the major priorities for any trauma patient; the burn wound is a secondary consideration. ) Verified burn centers are limited, making the management of severely burn injured patients at nonspecialized ICUs likely. Dressing . The purpose of this guideline is to update the previous guideline by Drs Faucher and Furukawa. The treatment of these patients is often protracted Nov 27, 2023 · Background Burn inhalation injury (BII) is a major cause of burn-related mortality and morbidity. A great deal of swelling is typical in the areas that are burned. Fluid resuscitation in the acute burn May 15, 2018 · Many burn-specific risk prediction models have been developed; however, these have predominantly been developed and validated in combined burn centre and burn unit patient populations 24 and little is known of their performance in burn patients admitted to an intensive care unit (ICU). 4 This is a reflection on the team approach to burn injuries, the resources, and infrastructure necessary to provide both critical care and the long-term management of the patient in terms of the planning and timing of surgical procedures. management of burn injuries may occur outside of specialist units, particularly for patients with a minor burn. The final questionnaire (32 questions) is provided in Additional file 1. Massive airway and/or lung edema can occur rapidly and unpredictably after burn and/or inhalation injury. Submitted March 25, 2010. Crit Care 2013;17:241. The pain is a fundamental aspect in the management of burn patients []. It is important for intensivists to be aware of the unique complications and therapeutic options in burn critical care management. The presence of diabetes and hyperglycemia has been known to be a risk factor for infectious complications in surgical patients. 2015;41(6):1107–9. 5. Mortality is increased if resuscitation is delayed longer than 2 hours post burn injury [ ]. It is seen in up to 70% of intensive care unit (ICU) pa-tients. 2–8. Care of burn-injured patients requires knowledge of the pathophysiologic changes affecting virtually all organs from the onset of injury until wounds are healed. In this short paper, we detail the key points of initial (0–48 h) critical care burn management (Fig. Second is the extent of the burn, usually expressed as the percentage of total body surface area (%TBSA) involved. Jun 6, 2018 · This finding seems consistent with the current literature, which still shows inadequate procedural pain management in general ICUs. One of the most important principles to remember with any burn patient is that they are a trauma and toxicology patient first. 1 Many require a protracted stay in intensive care, numerous operative interventions and comprehensive rehabilitation. A total of 160 patients from 28 ICUs in 16 countries were included. Clinical review: the critical care management of the burn patient. Mechanical prophylaxis: Sequential compression Oct 18, 2021 · Participants are 81 adult burn patients admitted to the Intensive Care Unit (ICU) of the University Hospital Fundación Santa Fe de Bogotá in Colombia. Without early and effective treatment, burns involving greater than 15 to 20% TBSA will result in hypovolaemic shock [ ]. However, severe burn injury requires care in specialized intensive care unit (ICU) due to the profound impact of burn injury on the body. 4 The mean burn size has been Location . It covers the incidence, causes, classification, effects and complications of burns. Inadequate agitation man-agement predisposes ICU patients to an increased risk of falls and of accidental or nagement of severely burn injured patients at nonspecialized ICUs likely. Feb 8, 2022 · The initial assessment and treatment of patients with major burns has been covered in a recent accompanying article. Burn-injured patients have a hypermetabolic response that automatically increases their core temperature (see Hypermetabolism in burn injury). Cohort A included all patients admitted to the BICU in our regional burn centre between 01/05/05 and 30/04/06. 4. One of the major challenges faced is confronting their hypermetabolic state and temperature management . [1][2][3] Burn severity classification is determined by the patient's age, the percentage of total body surface area burned (%TBSA), depth of burn, type of burn and Oct 7, 2013 · Appropriate fluid management is the foundation of acute burns management. They differ from the other critical care patient groups in several ways. There are ∼140 000 cases of new burns per year presenting to emergency departments in England and Wales, with around 10% of these being admitted to hospital. Facial and perineal burns. Next is the depth of the burn described as superficial (first degree), partial (second degree) or full thickness (third degree s. Burn care has seen renewed interest in colloid resuscitation, a change in transfusion pra … Jul 20, 2023 · As burn care has improved, patients with severe burn injury have had improved survival. Massive amounts of intravenous fluid are usually administered to replace intravascular volume deficit and to minimize complications attributed to hypovolemia such as tachycardia, hypotension, acute kidney injury, and multiorgan failure. or a cognitive disturbance. (See "Assessment and classification of burn injury". The mean length of stay in the ICU was 13. Dec 9, 2022 · Management and outcome in ICU and burn ward. the burn wound is a secondary consideration, although aseptic management of the burn wounds and invasive lines continues. Aim: To establish what outcomes are reported in published research that pertains to the intensive care management of patients with severe burns. Introduction Dec 16, 2021 · Results. 2 This article focuses on the ongoing care of an adult patient with a major burn of more than 15% total body surface area (TBSA) in both the operating theatre and the ICU. It is widely known that major burn injury is associated with the most profound of Jan 18, 2013 · There is controversy regarding whether milder degrees of fever secondary to infection or the systemic inflammatory response syndrome should be treated in critical care patients, as it may be part of a beneficial host response and treating it may not alter outcome. Proper evaluation and management, coupled with appropriate early referral to a specialist, greatly help in minimizing suffering and optimizing results. Jun 12, 2019 · The ABA reports that 40,000 patients were hospitalized with burns in 2016, and 30,000 of those patients were admitted to the 128 burn centers in the United States. Soussi et al. Improvement in initial Jun 7, 2012 · The care of the patient with major burns in the ICU is a complex and challenging task. Feb 23, 2012 · Inpatient burn injury care should be provided only by specialists trained in burn care in a burns unit. Oct 30, 2019 · Nursing the burn-injured patient and supporting his/her family throughout recovery is a complex, demanding, but ultimately, rewarding professional role. This chapter will focus on the initial resuscitation and management of severe burns. This study aimed to assess whether ventilation strategies, cardiovascular support and sedation in BICU patients have changed over time, and whether this affects outcome. In order to provide appropriate nutritional therapy to burn patients, it is important to understand the physiological and metabolic Jan 26, 2014 · Data were collected on two cohorts of burn intensive care unit (BICU) patients. Aug 2, 2010 · Fluid management. Demographic and admission May 1, 2013 · Background. The repertoire of nursing skills is varied and includes comprehensive critical care, complex wound care, pain and This Perspective gives an overview of burn care; focuses on pain and other symptoms in burn intensive care unit settings; addresses special needs of critically ill burned patients, their families, and clinicians for high-quality palliative care; and highlights potential benefits of integrating primary and specialist palliative care in burn Oct 2, 2020 · Elements of the pain assessment are as follows: Perform several times daily. Maintain appropriate nutritional support. Gabapentin is an agent that has been studied in both the acute and chronic management of burn pain. Introduction. Sep 14, 2022 · 3. Sep 30, 2015 · J Burn Care Res. One Hyperglycemia is commonly seen in the burn intensive care unit (BICU) as part of the burn inflammatory stress response. A recent and thorough review of the literature related to the ICU management of the burns patient in the UK, giving the reader an international perspective on burns care. Dec 1, 2015 · • Snell JA, Loh N-HW, Mahambrey T, Shokrollahi K. Almost 29,000 patients were admitted to UK burn services between 2003 and 2007 [1]. These guidelines are designed as a practical guide to complement relevant clinical knowledge and the care and management techniques required for effective patient management. Interestingly, even the These advances in burn care have improved burn survival from a near 100% mortality seen with a burn size of 30% in the early 1900s, 2 to survival estimates over 50% in young, healthy patients with burn sizes up to 95%. Patients with severe burns often receive complex management in intensive care unit (ICU) settings in the acute period after burn. Abuse occurs when a patient experiences adverse socioeconomic or health consequences related to the use of the substance. 3 [interquartile range (IQR) 6. 20,21 Moreover, a recent survey examining procedural pain management in burn patients 19 shows that only 25% of respondents used a systematic approach to managing procedural burn pain. A link to an electronic questionnaire was Aug 9, 2012 · Patients who are critically ill and admitted to an intensive care unit (ICU) have traditionally been placed on bed rest. 57 The estimated prevalence of pressure injuries among patients in the ICU is 16. Adult Guideline – Fluid Resuscitation in ICU; Adult Guideline – Guideline for Inhalation Injury in Burns Patients; Paediatric Guidelines. New data regarding common ICU issues A. Methods: This investigation is of a 9-year (2010–2019) retrospective preintervention and Management of pain during burn dressing changes is discussed in detail below ( preparing for a dressing change). Background: The objective of this study was to assess the quality of readily available evidence regarding critical care aspects of the management of patients with severe burn injuries. Assessing a patient's readiness to wake up and breathe on their own is an important part of the weaning process from mechanical ventilation support in the ICU. It also outlines the nursing management in the emergent/acute phase, which focuses on controlling the airway, breathing, circulation, disability and environment. It is widely known that major burn injury is associated with the most profound of May 29, 2016 · Outcomes for burn patients have improved dramatically over the past 20 years, yet burns still cause substantial morbidity and mortality. Apply white soft paraffin twice daily after cleaning face Chloramphenicol ointment to eye and ear burns Perineal burns are at risk of contamination – after bowel action, area should be cleaned with soapy solution; consider catheterisation Jun 16, 2021 · Serious burn injuries may have lifelong impacts for individuals that experience them and require timely medical treatment in order to reduce associated morbidity and mortality. Download references Patients with major burns (≥ 25% total body surface area) require management in an intensive care unit. Patients admitted to the burn center with burns more than 5% total body surface area and expected length Oct 6, 2023 · Modes of ventilation — Pulmonary management of patients with burns and inhalation injury may deviate from typical ventilator management practices in the general intensive care unit (eg, larger-than-typical tidal volumes). As healing Aug 28, 2020 · Daily awakening trials and discontinuation of sedation in mechanically ventilated intensive care unit patients may help reduce the length of their ICU stay. 05 days (ranging from a minimum of 17 hours to a maximum of 78 days). Jamie M. 1 – 3 Progression to sitting and standing often has been deferred in ICU populations until transfer to the floor, delaying mobility and increasing the risk for complications associated with immobility. To improve the morbidity and mortality of severely burned pediatric patients admitted to the pediatric intensive care unit, we created a specialized burn team. In Pakistan the practice of managing extensive burns in dedicated intensive care units is not well established. Cohort B covered all patients admitted to the same unit between 01/05/10 and 30/04/11. This summary aims to review the key principles in managing patients with severe burns including airway management, fluid resuscitation, sedation, burn care, analgesia and nutrition. Of 13 patients (including one patient from the burn ward) Admitted to ICU 8 was died and 5 transferred to the burn ward with improvement. Volume resuscitation of a patient with hypovolemic shock or sepsis is an essential component of patient care. Temperatures Feb 8, 2022 · As a result of improvements in the care of patients with major burns, increasing numbers of patients are surviving more severe injuries. Heffernan is the patient care director of the New York Presbyterian William Randolf Hearst Burn Center in Manhattan, and Odette Y. Major burns are systemic injuries requiring input from multiple specialities. May 26, 2022 · HAPIs are reportable adverse events that increase healthcare costs and in some cases result in financial penalties to hospitals. Hemodynamics in the early phase of severe burn injury is characterized by a reduction in cardiac output and increased The hallmarks of burn management include resuscitation, debridement, and nutrition. g. Preparation for Burns Dressing Preparation of patient and family. Insulin therapy has been demonstrated to improve outcomes in critically ill trauma patients1-3. Burn injuries create a sustained hypermetabolic response, leading to increased caloric and protein requirements. ICU Admission • Adult patients with burns ≥20% TBSA • Pediatric patients ≤5 yo with burns ≥10% TBSA • All pediatric patients with burns ≥15% TBSA • All intubated patients • Any patient requiring close monitoring of extremity perfusion (e. Jun 7, 2012 · The care of the patient with major burns in the ICU is a complex and challenging task. Critical Care (2018) 22:194 Page 3 of 3 Sep 1, 2016 · The objective of this study was to assess the quality of readily available evidence regarding critical care aspects of the management of patients with severe burn injuries. 1 Dependence is present either when the patient experiences withdrawal symptoms on discontinuation of the substance or when larger amounts are May 13, 2024 · Burn patients admitted to the Intensive Care Unit (ICU) are categorized as major burn victims if they have second-degree burns on more than 20% of the burned body surface area (TBSA) and third-degree burns on more than 10% of the TBSA; perineal burns; third-degree burns on hands, feet, face, neck, or armpits; or burns caused by electric shock . Care of the critically ill burned patient must integrate a multidisciplinary care team composed of burn care specialists. First is the type of burn, such as thermal, chemical, electrical, or radiation. Monitor for signs and symptoms of pneumonia. We would like to show you a description here but the site won’t allow us. 8%. Current practices in burn care have increased survivability even from massive burns. Method: PUBMED, EMBASE, Cochrane Databases and bibliographies of included studies and burns review articles were searched from inception of databases to end of Aug 1, 2020 · Management of burn patients in the ICU involves management of physiological derangements caused by burns, management of various catheters and tubes used for invasive monitoring, optimum nutrition along with local wound care. The intervention consists of a Music Assisted Relaxation (MAR) protocol, a music therapy technique composed of entrained live music combined with a guided relaxation and/or the use of imagery. Despite international collaborations and preventative measures, there are still many cases reported in high- and low-income countries. 20 To date, other than pain, no enzyme-related adverse event or complications that jeopardize burn Jul 16, 2024 · Stress ulcerations are common in intensive care unit (ICU) patients, some of which can cause hemorrhage. The use of gabapentin as an adjunct to standard analgesia has shown reduction in the severity neuropathic pain in limited studies of burn patients and burn injury models (Gray 2008, Dirks 2002). Burn survival correlates with 3 major factors: patient age, burn size, and presence of inhalation injury. 9 to 23. Engagement of a multidisciplinary burns team is necessary to help maximise quality of life for survivors who may have profound physiological Jan 16, 2024 · Patient-reported tools, such as the visual analog scale and the numeric rating scale, are commonly used as guides for pain management in burn patients. Epidermal or superficial dermal . Within the first 48h on ICU, no patients had their temperature fully maintained within the UHB range and in 16 patients (67%) it dropped below 36ºC at least once. Oct 7, 2013 · Between 4 and 22% of burn patients presenting to the emergency department are admitted to critical care. 1). 1 To accomplish this, we review the principles of acute pain management in adult burn patients and present a reasonable approach to the management of the complex pain associated with burn injury based on a review of the literature and expert opinion. ROLE IN BURN ICU - PATHOPHYSIOLOGY OF PAIN IN BURN PATIENTS. Ten tips for managing critically ill burn patients: follow the RASTAFARI! Intensive Care Med. Children and women are usually burned in domestic kitchens, from upset receptacles Feb 11, 2022 · The purpose of this study was to determine ambient patient room temperatures in a burn intensive care unit (ICU) and to evaluate our ability to adjust these temperatures. 4 An elevated core temperature in certain subgroups of patients such as in Mar 25, 2014 · This document discusses the nursing management of patients with burns. Comeau is an adult critical care clinical nurse specialist at University of Texas Medical Branch. The 35 kcal/kg BW equation was suitable for young patients with burns over >50%TBSA in the ICU because it could be applied without equivocation, in time, and with acceptable wound healing rates. Jan 5, 2023 · This Clinical Practice Guideline addresses early mobilization and rehabilitation (EMR) of critically ill adult burn patients in an intensive care unit (ICU) setting. Mar 4, 2022 · Pre-specified protocol: Patient-centred core outcomes are under-reported in the critical care burns literature: a systematic review. Sep 4, 2020 · PURPOSE. Experts of the European Society of Intensive Care Medicine (ESICM) Burn ICU working group were invited to review the original survey. Sep 26, 2020 · The critical care in a severely burn-injured patient requires special attention in resuscitation, haemodynamic monitoring, management of complications, organ support and determinants of outcome. We defined EMR as any systematic or protocolized intervention that could include muscle activation, active exercises in bed, active re … Aug 15, 2019 · Electrical burns, including lightning injury Chemical burns Inhalation injury Burn injury in patients with preexisting medical disorders that could complicate management, prolong recovery, or affect mortality Any patient with burns and concomitant trauma (such as fractures) in which the burn injury poses the greatest risk of morbidity or mortality* Abstract. Method PUBMED, EMBASE, Cochrane Databases and bibliographies of included studies and burns review articles were searched from inception of databases to end of February 2015. Of these, 4000–5000 cases are complex and require the services of a regional adult burns unit. Burn injury is characterised by a hypermetabolic response with physiologic, catabolic and immune effects. As a consequence, many critically ill patients require prophylaxis for primary prevention of bleeding from stress ulceration or treatment for stress ulcer-related bleeding. Compliance to the optimal the critical care management of severe burns, touching on accurate diagnosis, resuscitation, and acute management of this difficult patient population. view of the recent burn literature tailored to the critical care practitioner. May 21, 2019 · Resuscitation of the Burn and Inhalation Injuries Patient. Introduction and objectives. One of the fundamental pillars in the treatment of patients with acute burns is effective pain management, which also requires indirect early management of short-term complications derived from ineffectual management, including venous thrombosis, hypertension with target organ, tachycardia, coronary event, hyperglycemia, immunosuppression, as well as of the long Burns occur mainly in the home and workplace. Community surveys in Bangladesh and Ethiopia show that 80– 90% of burns occur at home. Clinicians working outside a specialist burn unit are Dec 16, 2021 · A total of 160 patients from 28 ICUs in 16 countries were included. 3] mL/kg PBW and did not differ between patients with and without inhalation trauma (p = 0. [2] Sep 4, 2011 · Burn injuries continue to cause morbidity and mortality internationally. Despite published practice guidelines, no consensus exists for the best strategies regarding diagnosis and management of BII. Methods: The ambient temperatures of 9 burn ICU patient rooms were recorded hourly over a 6-month period in an American Burn Association-verified burn centre. je ub sj ug qa nq pd xg ik ws