Despite of the cardiovascular and neurological risks implicated by the beach chair position, surgical operations of specific cases (commonly shoulder arthroplasty) still prefer to perform the procedure using the beach chair position. According to Lobato, Gravenstein and Kirby (2007), beach chair position is a potentially important contributing factor to the reduction of cerebral perfusion, it has significant advantages for the orthopedic surgeon due to the aid of arm’s weight in distract the joints and avoiding distortion of intra-articular anatomy (p. 856).
Despite of the risks of hypotension and VAE, the use of sitting position during surgery is still preferred due to the following reasons (1) anatomic positioning providing immediate access, and better visualization and manipulation of the site, (2) disregards the use of traction, (3) conversion to an open surgical procedure from beach chair position is seamless avoiding the need to either reposition or redrape the patient (e. g. glenohumeral surgery) and (4) complements both general or regional anesthesia (Tibone, McCarthy and Savoie, 2003 p. 9).
According to Yao, Malhotra and Fontes (2005), due to the beneficial effects of gravity, pulmonary compliance and functional residual capacity are greater in the sitting position than in the supine surgical positioning; however, the simultaneous cardiovascular effects may trigger the increased ventilation-perfusion mismatch, which in the essence counters the pulmonary compliance and residual benefits of sitting position (p. 535).
The anatomic nature in sitting positioning allows better orientation and understanding of upper extremity anatomy; hence, facilitating greater ease in examinations under anesthesia. In fact, due to the simplicity and conversion options of sitting position, the beach chair position has become the standard position for some arthroplasty procedures, especially on shoulder arthroplasty. Meanwhile, according to Craig (2003), beach chair positioning prevents potential neural complications that may occur when patient is in decubitus position, especially with arm traction (p. 8).
Significant advantage of sitting position is the possibility of reducing the distraction of joints and prevention of distortion of the intra-articular anatomy. In addition, beach chair position offers the advantage of easy airway management and easy access, especially for arthrotomy, while providing the efficient anatomic visualization of intra-articular structures (Imhoff, Ticker and Fu, 2003 p. 71). According to Finlay, Kneedler and Dodge (1998), sitting position provides immediate access in operating the preferred section of the body.
Moreover, the use of sitting position provides immediate reconstructive positioning due to the flexibility of positioning. According to Imoff, Ticker and Fu (2003), hypotension and VAE risks are still regarded as another consideration in the use of beach chair positioning; however, various methods are available aiming to prevent the risks and dangers of the said positioning (e. g. refrain in using hypotensive anesthetics, administration of anti-gravity suits to prevent venous pooling, etc. ). II. Synthesis and Conclusion of Related Literature
Sitting position or beach chair position is surgical positioning designed to expose the upper anatomical sections of the body for better viewing, operation and scope of view. Surgical operations, such as shoulder arthroscopy, laminectomy, cranial fossa surgery, etc, are some of the most common cases that utilize sitting or beach chair positioning. However, despite of the beneficial provisions of sitting position during surgery, disadvantages and risk factors become another controversial issue in the use of such positioning.
Hypotension and venous air embolism are the most common forms of physiological complications associated to the venous pooling and decline of MAP. In fact, the most common areas affected by the complications of beach chair position mainly include (1) MAP and (2) thoracic pressures – intrathoracic and extrathoracic. The effects on MAP and thoracic pressures further trigger consequent decline in cardiac output, stroke output volume, vascular pressure and peripheral resistance.
However, despite of the disadvantages and deadly risks, surgeons still prefer to use such positioning due to the following benefits: 1. Anatomic positioning providing immediate access, and better visualization and manipulation of the site 2. Disregards the use of traction 3. Conversion to an open surgical procedure from beach chair position is seamless avoiding the need to either reposition or redrape the patient 4. Complements both general or regional anesthesia.
Furthermore, some researchers mentioned in the study consider the rarity of complications arising from sitting position. In fact, some complications that arise usually dissipate during the post-operative condition until recovery. However, the literature review has found the lack of study pertaining to the trends of MAP in conjunction to the effects of surgical sitting position; hence, study on MAP trends on patients under surgical operation while sitting is an essential consideration.
References
Abrams, W. J. , & Nottage, W. (2003, August). Complications associated with arthroscopic shoulder surgery. Arthroscopy: The Journal of Arthroscopic & Related Surgery, 18, 88-95. Bithal, P. K. , Pandia, M. P. , & Dash et al. , H. H. (2004, May). Comparative incidence of venous air embolism and associated hypotension in adults and children operated for neurosurgery in the sitting position. British Journal of Anaesthesia, 21, 517-522.