Serial measurement of Therapeutic Intervention Scoring System-28 (TISS-28) in a surgical intensive care unit

Abstract

Purpose

The aim of the study was to assess the use of the Therapeutic Intervention Scoring System-28 (TISS-28) in surgical intensive care unit (ICU) patients and the relationship of the score to the type of surgery, severity of illness, and outcome in these patients.

Materials and Methods

Prospectively collected data from all patients admitted to a postoperative ICU between March 1, 2004, and June 30, 2006, were analyzed retrospectively.

Results

A total of 6903 patients were admitted during the study period (63.5% male; mean age, 62.3 years) constituting 29 140 observation days. The mean Simplified Acute Physiology Score (SAPS) II, Sequential Organ Failure Assessment (SOFA), and TISS-28 scores on the day of ICU admission were 36.9 ± 18.2, 5.8 ± 3.9, and 43.2 ± 10.8, respectively. The highest admission TISS-28 was observed in patients who underwent cardiothoracic surgery (47.7 ± 10.1), the lowest in neurosurgical patients (40 ± 9.6), and both declined during the 2 weeks after ICU admission; however, in trauma patients and those admitted after gastrointestinal surgery, TISS scores increased gradually after the first 2 to 5 days in the ICU. The TISS-28 score was moderately correlated to SAPS II (R² = 0.42; P < .001) and SOFA score (R² = 0.48; P < .001) throughout the ICU stay and was consistently higher in nonsurvivors than in survivors during the first 2 weeks in the ICU.

Conclusions

There are marked variations in TISS-28 scores according to the type of surgery. Therapeutic Intervention Scoring System-28 correlates with the severity of illness and outcome in these patients.

Introduction

Over the last few decades, several scoring systems have been developed for use in critically ill patients not only to assist therapeutic decision making but also to guide resource allocation and quality of care [1]. The Therapeutic Intervention Scoring System (TISS) was developed by Cullen and colleagues [2] in 1974 from a list devised by a panel of experts and includes 76 therapeutic activities performed in the intensive care unit (ICU) [3]. A simplified version was created by Miranda et al [4] using 28 items from a random sample of 10 000 records of TISS-76 and validated to distinguish between different degrees of nursing workload [4], [5]; the TISS-28 has replaced the original TISS-76 in clinical practice.

Several studies have assessed the use of TISS-28 in the ICU in evaluating nursing workload [4], resource use [6], [7], mechanical ventilatory support [8], [9], transport risks [10], [11], and severity of illness and prognosis [12]. However, few studies have evaluated TISS-28 in the postoperative ICU setting [7], [13], [14]. Moreover, serial assessment of TISS-28 during the ICU stay and the relationship of the score to the type of surgery, severity of illness, and mortality have never been reported in these patients. These data may be helpful in ICU planning, risk stratification, and resource allocation.

The aim of our study was, therefore, to evaluate serial TISS-28 measurements in a surgical ICU and to assess the possible relationship between TISS-28 and the type of surgery, severity of illness, and outcome in these patients.