Follow the minimum monitoring standards; use the pulse oximeter
Abstract
Sir,
Minimum Mandatory Monitoring Standards (MMMS) have been formulated globally and at various national levels of the developing nations.1 A minimum monitoring with an ECG, a pulse oximeter and a non-invasive blood pressure monitoris mandatory according to these standards.2 The question, “Is the pulse oximeter on the patient and functioning?” is an essential item in the WHO surgical safety checklist.3 We report an incident highlighting importance of MMMS, especially the use of pulseoximetry.
A 30 year old male sustained a fracture shaft of his left femurand pubic ramiand was posted for closed reduction and internal fixation. Preoperative evaluation was unremarkable. He had Hb13.1 g/dl, anormal ECG and normal radiograph of chest. As an ASAgrade 1 patient, a combined spinal – epidural technique was planned for him. On the operating table, the patient was connected to monitoring devices according to MMMS. He was mildly febrile with a pulse rate 136/minute, BP110/80 mm Hg, respiratory rate 18 breaths/min and SpO2 88% on room air. The saturation improved to 92% on oxygenation through face mask. His chest was clear on auscultation and he appeared comfortable. We attached the probe on multiple sites but the pulseoximeter continued to show low readings. We deferred the case for further investigation. Next day a 2D-echocardiographywas done and it revealed mild pulmonary artery hypertension with a PASP of 40 mmHg. A CT pulmonary angiogram revealed pulmonary embolism involving the left inferior pulmonary artery with extension into the lobar and segmental arteries(Figure 1). After a cardiologist consultation, the patient was started on intravenousunfractionated heparin for fivedays. After whichhe was posted for surgery. This time the SpO2 was 98% on room air preoperatively andthe surgerywent uneventfully.
Early detection and correction of perioperative events through the use ofpulse oximetryis improves patient outcomes.4The clinical manifestations of pulmonary embolism are not always definitive or specific. It may present silently and maybe missed by the clinicians.5 Our case is an apt example of a situation where the pulseoximeter used as a part of the MMMS helped in diagnosis and avoidance of an untoward outcome.
It isnowonder then, that many authors have complimented the pulseoximeter by saying “Having an oximeter is like having a skilled pair of hands”4and “Always keep a finger on the patient’s pulse and a pulseoximeter on the patient’s fingers”.2
Our case conveys an important message to all practicing anesthesiologists -“Follow the guidelines if you want to be safe” and “Make liberal use of the pulse oximeter from the preinduction period upto the postoperative period”.
